SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549

                                 ------------

                                  SCHEDULE 13G


           INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
            TO RULES 13d-1(b), (c) AND (d) AND AMENDMENTS THERETO
                         FILED PURSUANT TO RULE 13d-2(b)

                              (AMENDMENT NO. ___)(1)

                PRIMUS TELECOMMUNICATIONS GROUP, INCORPORATED
                                (Name of Issuer)


                   COMMON STOCK, PAR VALUE $0.01 PER SHARE
                         (Title of Class of Securities)


                                  741929 103
                                 (CUSIP Number)


                                  JUNE 9, 1998
           (Date of Event Which Requires Filing of this Statement)


    Check  the  appropriate  box  to  designate  the rule pursuant to which this
Schedule is filed:

                  |_| Rule 13d-1(b)

                  |_| Rule 13d-1(c)

                  |X| Rule 13d-1(d)



- ---------------------

      (1) The  remainder  of this cover page shall be filled out for a reporting
person's  initial  filing on this  form with  respect  to the  subject  class of
securities,  and for any subsequent amendment containing information which would
alter the disclosures provided in a prior cover page.

        The  information  required in the remainder of this cover page shall not
be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange
Act of 1934 or otherwise  subject to the  liabilities of that section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  SEE the
NOTES).




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CUSIP NO. 741929 103                   13G            PAGE 2 OF 7 PAGES
- -----------------------------------            --------------------------------


- -------------------------------------------------------------------------------
       1.     NAMES OF REPORTING PERSONS
              I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

              Warburg, Pincus Investors, L.P.
              I.D. No. 13-3549187
- -------------------------------------------------------------------------------
       2.     CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*  (a)  |_|
                                                                 (b)  |X|

- -------------------------------------------------------------------------------
       3.     SEC USE ONLY

- -------------------------------------------------------------------------------
       4.     CITIZENSHIP OR PLACE OF ORGANIZATION

              Delaware
- -------------------------------------------------------------------------------
                       5.   SOLE VOTING POWER
    NUMBER OF
                            0
     SHARES        ------------------------------------------------------------
                       6.   SHARED VOTING POWER
  BENEFICIALLY
                            3,875,689
    OWNED BY       ------------------------------------------------------------
                       7.   SOLE DISPOSITIVE POWER
      EACH
                            0
   REPORTING       ------------------------------------------------------------
                       8.   SHARED DISPOSITIVE POWER
  PERSON WITH
                            3,875,689
- -------------------------------------------------------------------------------
       9.     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

              3,875,689
- -------------------------------------------------------------------------------
       10.    CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 9 EXCLUDES CERTAIN 
              SHARES*                                                   |_|

- -------------------------------------------------------------------------------
       11.    PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

              13.8%
- -------------------------------------------------------------------------------
       12.    TYPE OF REPORTING PERSON*

              PN
- -------------------------------------------------------------------------------

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!





- -----------------------------------            --------------------------------
CUSIP NO. 741929 103                   13G            PAGE 3 OF 7 PAGES
- -----------------------------------            --------------------------------


- -------------------------------------------------------------------------------
       1.     NAMES OF REPORTING PERSONS
              I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

              Warburg, Pincus & Co.
              I.D. No. 13-6358475
- -------------------------------------------------------------------------------
       2.     CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*  (a)  |_|
                                                                 (b)  |X|

- -------------------------------------------------------------------------------
       3.     SEC USE ONLY

- -------------------------------------------------------------------------------
       4.     CITIZENSHIP OR PLACE OF ORGANIZATION

              New York
- -------------------------------------------------------------------------------
                       5.   SOLE VOTING POWER
    NUMBER OF
                            0
     SHARES        ------------------------------------------------------------
                       6.   SHARED VOTING POWER
  BENEFICIALLY
                            3,875,689
    OWNED BY       ------------------------------------------------------------
                       7.   SOLE DISPOSITIVE POWER
      EACH
                            0
   REPORTING       ------------------------------------------------------------
                       8.   SHARED DISPOSITIVE POWER
  PERSON WITH
                            3,875,689
- -------------------------------------------------------------------------------
       9.     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

              3,875,689
- -------------------------------------------------------------------------------
       10.    CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 9 EXCLUDES CERTAIN 
              SHARES*                                                   |_|

- -------------------------------------------------------------------------------
       11.    PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

              13.8%
- -------------------------------------------------------------------------------
       12.    TYPE OF REPORTING PERSON*

              PN
- -------------------------------------------------------------------------------

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!



- -----------------------------------            --------------------------------
CUSIP NO. 741929 103                   13G            PAGE 4 OF 7 PAGES
- -----------------------------------            --------------------------------


- -------------------------------------------------------------------------------
       1.     NAMES OF REPORTING PERSONS
              I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

              E.M. Warburg, Pincus & Co., LLC
              I.D. No. 13-3536050
- -------------------------------------------------------------------------------
       2.     CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*  (a)  |_|
                                                                 (b)  |X|

- -------------------------------------------------------------------------------
       3.     SEC USE ONLY

- -------------------------------------------------------------------------------
       4.     CITIZENSHIP OR PLACE OF ORGANIZATION

              New York
- -------------------------------------------------------------------------------
                       5.   SOLE VOTING POWER
    NUMBER OF
                            0
     SHARES        ------------------------------------------------------------
                       6.   SHARED VOTING POWER
  BENEFICIALLY
                            3,875,689
    OWNED BY       ------------------------------------------------------------
                       7.   SOLE DISPOSITIVE POWER
      EACH
                            0
   REPORTING       ------------------------------------------------------------
                       8.   SHARED DISPOSITIVE POWER
  PERSON WITH
                            3,875,689
- -------------------------------------------------------------------------------
       9.     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

              3,875,689
- -------------------------------------------------------------------------------
       10.    CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 9 EXCLUDES CERTAIN 
              SHARES*                                                   |_|

- -------------------------------------------------------------------------------
       11.    PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

              13.8%
- -------------------------------------------------------------------------------
       12.    TYPE OF REPORTING PERSON*

              00
- -------------------------------------------------------------------------------

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!



- -----------------------------------            --------------------------------
CUSIP NO. 741929 103                   13G            PAGE 5 OF 7 PAGES
- -----------------------------------            --------------------------------

ITEM 1(a).  NAME OF ISSUER.

            Primus Telecommunications Group, Incorporated, a Delaware
            corporation (the "Issuer").

ITEM 1(b).  ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES.

            1700 Old Meadow Road
            Suite 300
            McLean, Virginia  22102

ITEMS 2(a)
 AND 2(b).  NAME OF PERSON FILING; ADDRESS OF PRINCIPAL BUSINESS OFFICE.

            This  statement  is filed by and on  behalf of (a)  Warburg,  Pincus
            Investors,   L.P.,  a  Delaware  limited  partnership  ("WPI");  (b)
            Warburg,  Pincus & Co., a New York general  partnership  ("WP"); and
            (c) E.M.  Warburg,  Pincus & Co., LLC, a New York limited  liability
            company ("EMW LLC"), which manages WPI. WP, the sole general partner
            of WPI,  has a 20%  interest  in the  profits of WPI, as the general
            partner.  Lionel  I.  Pincus  is the  managing  partner  of WP,  the
            Chairman of the Board,  Chief  Executive  Officer  and the  managing
            member of EMW LLC and may be deemed to control  both WP and EMW LLC.
            The members of EMW LLC are substantially the same as the partners of
            WP. The business  address of each of the  foregoing is 466 Lexington
            Avenue, New York, New York 10017.

ITEM 2(c).  CITIZENSHIP.

            Not Applicable.

ITEM 2(d).  TITLE OF CLASS OF SECURITIES.

            This statement  relates to shares of the Issuer's common stock,  par
            value $0.01 per share (the "Common Stock").

ITEM 2(e).  CUSIP NUMBER.

            741929 103

ITEM 3.     Not Applicable.

ITEM 4.     OWNERSHIP.

            (a)  Amount Beneficially Owned:

            3,875,689 shares of Common Stock, as of December 31, 1998.



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CUSIP NO. 741929 103                   13G            PAGE 6 OF 7 PAGES
- -----------------------------------            --------------------------------



            (b)  Percent of Class:

            13.8% (based on the number of shares of Common Stock  reported to be
            outstanding  in the Issuer's Form 10-Q for the fiscal  quarter ended
            September 30, 1998).

            (c)   (i)   0
                  (ii)  3,875,689
                  (iii) 0
                  (iv)  3,875,689

ITEM 5.     OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS.

            Not Applicable.

ITEM 6.     OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON.

            Not Applicable.
ITEM 7.     IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH
            ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING
            COMPANY.

            Not Applicable.

ITEM 8.     IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP.

            Not Applicable.

ITEM 9.     NOTICE OF DISSOLUTION OF GROUP.

            Not Applicable.

ITEM 10.    CERTIFICATIONS.

            Not Applicable.




- -----------------------------------            --------------------------------
CUSIP NO. 741929 103                   13G            PAGE 7 OF 7 PAGES
- -----------------------------------            --------------------------------

                                    SIGNATURE

            After reasonable inquiry and to the best of my knowledge and belief,
I certify that the information set forth in this statement is true, complete and
correct.


Dated:  February 9, 1999            WARBURG, PINCUS INVESTORS, L.P.
                                      By: Warburg, Pincus & Co., General Partner



                                      By:/s/ Stephen Distler
                                         ---------------------------------------
                                            Stephen Distler, Partner



Dated:  February 9, 1999            WARBURG, PINCUS & CO.



                                      By:/s/ Stephen Distler
                                         ---------------------------------------
                                             Stephen Distler, Partner



Dated:  February 9, 1999            E.M. WARBURG, PINCUS & CO., LLC



                                      By:/s/ Stephen Distler
                                         ---------------------------------------
                                             Stephen Distler, Member




                                    SCHEDULES


Schedule I      Joint  Filing  Agreement,  dated  February  9,  1999,  among 
                the signatories of this Schedule 13G.





                             JOINT FILING AGREEMENT
                          PURSUANT TO RULE 13d-1(k)(1)


   The  undersigned  acknowledge  and  agree  that the  foregoing  statement  on
Schedule  13G is  filed  on  behalf  of each of the  undersigned  and  that  all
subsequent amendments to this statement on Schedule 13G shall be filed on behalf
of each of the  undersigned  without the  necessity of filing  additional  joint
filing  agreements.  The undersigned  acknowledge that each shall be responsible
for the timely filing of such amendments,  and for the completeness and accuracy
of the information concerning it contained therein, but shall not be responsible
for the  completeness  and accuracy of the  information  concerning  the others,
except  to the  extent  that  it  knows  or has  reason  to  believe  that  such
information  is  inaccurate.  This  Agreement  may be  executed in any number of
counterparts  and all of such  counterparts  taken together shall constitute one
and the same instrument.

Dated: February 9, 1999              WARBURG, PINCUS INVESTORS, L.P.
                                       By: Warburg, Pincus & Co., General
Partner



                                       By:/s/ Stephen Distler
                                          --------------------------------------
                                             Stephen Distler, Partner



                                       WARBURG, PINCUS & CO.



                                       By:/s/ Stephen Distler
                                          --------------------------------------
                                             Stephen Distler, Partner



                                       E.M. WARBURG, PINCUS & CO., LLC



                                       By:/s/ Stephen Distler
                                          --------------------------------------
                                             Stephen Distler, Member