FORM 6 - K

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                        Report of Foreign Private Issuer
                    Pursuant to Rule 13a - 16 or 15d - 16 of
                       the Securities Exchange Act of 1934

                               As of April 7, 2003

                                  TENARIS, S.A.
                 (Translation of Registrant's name into English)

                                  TENARIS, S.A.
                               23 Avenue Monterey
                                 2086 Luxembourg
                    (Address of principal executive offices)

        Indicate by check mark whether the registrant files or will file
                 annual reports under cover Form 20-F or 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): 82-__________.



The attached material is being furnished to the Securities and Exchange
Commission pursuant to Rule 13a-16 and Form 6-K under the Securities Exchange
Act of 1934, as amended. This report contains Tenaris's announcing advance
purchase of natural gas in Argentina

                                    SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned, thereunto duly authorized.

Date: April 7, 2003

                                  Tenaris, S.A.

By: /s/ Cecilia Bilesio
- ------------------------------
Cecilia Bilesio
Corporate Secretary

                                                                    Exhibit 99.1

Gerardo Varela
Tenaris
1-888 300 5432
www.tenaris.com

Tenaris Announces Advance Purchase of Natural Gas in Argentina

Luxembourg,  April 4, 2003. - Tenaris (TS: NYSE,  Buenos Aires,  Mexico and TEN:
MTA Italy) announced today that its subsidiary,  Siderca  S.A.I.C.,  has entered
into a contract with Tecpetrol S.A. for the advance  purchase of natural gas for
use in its operations in Argentina. The contract covers the provision of natural
gas to Siderca's  seamless steel pipe  facilities and its  newly-acquired  power
generation  facility for a period of five years. Under the terms of the contract
Tecpetrol will supply the balance of Siderca's natural gas requirements that are
not supplied by its principal gas supplier,  RepsolYPF. Siderca will pay US$15.3
million as an advance for the purchase of 760 million cubic meters over the five
year period.

Through this advance  purchase,  Tenaris will secure the supply of a significant
proportion of its  requirements  for natural gas in its  operations in Argentina
over the next five years on  pricing  conditions  under  which the impact of any
future  increases in Argentine  natural gas prices from their current low levels
will be limited by being shared between buyer and seller.

Tecpetrol S.A. is a  privately-held  company of the Techint Group,  with oil and
gas  exploration  and production  activities in Argentina and other countries in
South America. As a related party transaction,  the contract was approved by the
independent members of Siderca's board of directors in accordance with Argentine
corporate governance provisions.

With manufacturing facilities in Argentina, Brazil, Canada, Italy, Japan, Mexico
and  Venezuela  and a network of  customer  service  centers  present in over 20
countries worldwide,  Tenaris is a leading global manufacturer of seamless steel
pipes and provider of pipe handling,  stocking and distribution  services to the
oil and gas,  energy and  mechanical  industries  as well as a leading  regional
supplier of welded steel pipes for gas pipelines in South America.