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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                            _______________________

                                    FORM 6-K

       REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 or 15d-16
                   UNDER THE SECURITIES EXCHANGE ACT OF 1934
                            _______________________

                        Date of Report: December 9, 2004

                              CEMEX, S.A. de C.V.
                              ___________________
             (Exact name of Registrant as specified in its charter)

                                  CEMEX Corp.
                                  ___________
                (Translation of Registrant's name into English)

                             United Mexican States
                             _____________________
                (Jurisdiction of incorporation or organization)

          Av. Ricardo Margain Zozaya #325, Colonia del Valle Campestre
                     Garza Garcia, Nuevo Leon, Mexico 66265
          ____________________________________________________________
                    (Address of principal executive offices)


Indicate by check mark whether the registrant files or will file annual reports
under cover Form 20-F or Form 40-F.

Form 20-F __X__      Form 40-F ___

Indicate by check mark whether the registrant by furnishing the information
contained in this Form is also thereby furnishing the information to the
Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of
1934.

Yes ____              No __X__

If "Yes" is marked, indicate below the file number assigned to the registrant
in connection with Rule 12g3-2(b):

N/A
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Contents 1. Press release issued by CEMEX, S.A. de C.V. ("CEMEX") and RMC Group p.l.c. ("RMC"), dated December 9, 2004, announcing that the European Commission ("EC") cleared the acquisition of RMC by CEMEX UK Limited, a wholly-owned subsidiary of CEMEX, under the EC Merger Regulation (attached hereto as exhibit 1).

SIGNATURE Pursuant to the requirements of the Securities Exchange Act of 1934, CEMEX, S.A. de C.V. has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized. CEMEX, S.A. de C.V. ______________________________ (Registrant) Date: December 9, 2004 By: /s/ Rafael Garza __________________________ Name: Rafael Garza Title: Chief Comptroller

EXHIBIT INDEX EXHIBIT NO. DESCRIPTION - ----------- ----------- 1 Press release issued by CEMEX, S.A. de C.V. ("CEMEX") and RMC Group p.l.c. ("RMC"), dated December 9, 2004, announcing that the European Commission ("EC") cleared the acquisition of RMC by CEMEX UK Limited, a wholly-owned subsidiary of CEMEX, under the EC Merger Regulation.

                                                                   EXHIBIT 1



                    RMC Group p.l.c. and CEMEX, S.A. de C.V.

09 December 2004



         NOT FOR RELEASE, PUBLICATION OR DISTRIBUTION IN, INTO OR FROM
                           AUSTRALIA, CANADA OR JAPAN

                             FOR IMMEDIATE RELEASE



        RECOMMENDED ACQUISITION OF RMC GROUP p.l.c. BY CEMEX UK LIMITED,
                      A SUBSIDIARY OF CEMEX, S.A. de C.V.



                               REGULATORY UPDATE


RMC and CEMEX are pleased to announce that the European Commission cleared the
Acquisition yesterday under the EC Merger Regulation.

The Acquisition remains under review by the US anti-trust authorities and
clearance under applicable US anti-trust legislation is expected in time for
the Scheme to become effective on 12 January 2005. If this position changes, a
further announcement will be made.

Terms used in this announcement shall have the same meanings as set out in the
Scheme document dated 25 October 2004.



Enquiries:

RMC
Gary Rawlinson (Investor Relations)           Tel: +44 (0) 1932 568 833
Tim Stokes (Media Relations)


Cazenove                                      JPMorgan
(Financial Adviser and Corporate Broker       (Financial Adviser to RMC)
to RMC)
Tel: +44 (0) 20 7588 2828                     Tel: +44 (0) 20 7742 4000
Nick Wiles                                    Robert McGuire
Piers Coombs                                  Henry Lloyd
Roger Clarke                                  Eamon Brabazon


Hoare Govett
(Corporate Broker to RMC)                     Tel: +44 (0) 20 7601 0101
Peter Meinertzhagen
Chris Zeal


Citigate Dewe Rogerson
(PR Adviser to RMC)                           Tel: +44 (0) 20 7638 9571
Jonathan Clare
Michael Berkeley


CEMEX
Javier Trevino (Media Relations)              Tel: +44 (0) 20 7379 5151
Maher Al-Haffar (Investor Relations)          Tel: +1 212 317 6006


Citigroup                                     Goldman Sachs International
(Financial Adviser and Corporate Broker       (Financial Adviser and Corporate
to CEMEX and CEMEX UK)                        Broker to CEMEX and CEMEX UK)
Tel: +44 (0) 20 7986 4000                     Tel: +44 (0) 20 7774 1000
Philip Robert-Tissot                          Simon Dingemans
Cyrus Shabi                                   Basil Geoghegan
Jan Skarbek

The Maitland Consultancy
(PR Adviser to CEMEX and CEMEX UK)            Tel: +44 (0) 20 7379 5151
Angus Maitland
Philip Gawith


The directors of RMC accept responsibility for the information contained in
this announcement and confirm that, to the best of their knowledge and belief
(having taken all reasonable care to ensure that such is the case), the
information contained in this announcement is in accordance with the facts and
does not omit anything likely to affect the import of such information.

The directors of CEMEX UK and the directors of CEMEX accept responsibility for
the information contained in this announcement relating to CEMEX UK and CEMEX.
To the best of the knowledge and belief of the directors of CEMEX UK and the
directors of CEMEX (who have taken all reasonable care to ensure that such is
the case), the information contained in this announcement for which they are
responsible is in accordance with the facts and does not omit anything likely
to affect the import of such information.

Cazenove, which is regulated by the Financial Services Authority, is acting as
financial adviser and corporate broker to RMC in connection with the
Acquisition and no one else and will not be responsible to anyone other than
RMC for providing the protections afforded to customers of Cazenove or for
providing advice in relation to the Acquisition, or the contents of this
announcement.

JPMorgan, which is regulated by the Financial Services Authority, is acting as
financial adviser to RMC in connection with the Acquisition and no one else and
will not be responsible to anyone other than RMC for providing the protections
afforded to customers of JPMorgan or for providing advice in relation to the
Acquisition, or the contents of this announcement.

Hoare Govett, which is regulated by the Financial Services Authority, is acting
as corporate broker to RMC in connection with the Acquisition and no one else
and will not be responsible to anyone other than RMC for providing the
protections afforded to customers of Hoare Govett or for providing advice in
relation to the Acquisition, or the contents of this announcement.

Citigroup and Goldman Sachs International, which are regulated by the Financial
Services Authority, are acting as financial advisers and corporate brokers to
CEMEX and CEMEX UK in connection with the Acquisition and no one else and will
not be responsible to anyone other than CEMEX and CEMEX UK for providing the
protections afforded to their respective customers or for providing advice in
relation to the Acquisition, or the contents of this announcement.