EXHIBIT 4.4

**Unofficial English translation of agreements originally drawn up in Spanish. In case of discrepancy the Spanish language version prevails**

**SECOND ADDENDUM TO THE REPLACEMENT AGREEMENT BETWEEN**

**REPSOL YPF S.A. AND “LA  CAIXA” DATED JANUARY 11, 2000**

This second addendum is made by and between Antonio Brufau Niubó, in representation and on behalf of Caixa d’Estalvis i Pensions de Barcelona, hereinafter “La Caixa,” party of the first part,

and

Ramón Blanco Bahia, in representation and on behalf of Repsol YPF S.A., party of the second part,

With both parties acknowledging that each has sufficient legal capacity to make this addendum, and

W H E R E A S:

1.  On May 16, 2002, the  parties signed a “Replacement Agreement between Repsol YFP, S.A. and La  Caixa dated January 11, 2000,” with regard to Gas Natural SDG, S.A. Said  replacement formed the subject matter of an Addendum dated December 16, 2002;

2.  The parties are desirous  of continuing the Agreement of May 16, 2002, entitled “Replacement Agreement  between Repsol YFP, S.A. and La Caixa dated January 11, 2000,” insofar  as relates now to the entry on the Board of Gas Natural SDG, S.A., of a Board  member outside those nominated by the parties, who has already been advanced,  and thereby to amend some of the agreements in an effort to adapt better to  any situation that may arise,

NOW, THEREFORE, the parties AGREE AS FOLLOWS:

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1.  The parties agree to  appoint La Caixa de Catalunya as a Board member of Gas Natural SDG, S.A., which  together with HISUSA Holding de Infraestructuras y Servicios Urbanos, S.A.,  would be able to become holders of respectively three percent (3%) and five  percent (5%) of the stock capital of Gas Natural SDG, S.A. Consequently, this  appointment shall be voted upon at the General Meeting to be held on the 23rd  of June next, with the understanding that involved here in any case is an appointment  that has to be granted to La Caixa de Catalunya.

As a result of the foregoing, the Board of Directors will be composed of seventeen (17) members, with sixteen (16) of them provided for in the Addendum of December 16, 2002, plus La Caixa de Catalunya.

2.  The second stipulation  of the Replacement Agreement of May 16, 2002, will now contain the following  language:

|   | *“II - LINES OF BUSINESS ACTIONS.*                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|   | *“In accordance with      said principles, the parties agree in good faith and bearing in mind the      very interests of Gas Natural SDG S.A., prior to submission to the Board,      to the strategic plan of Gas Natural SDG, S.A., which will include all decisions      that affect the corporation’s basic lines of strategy, its organizational      structure, the annual budget, the concentration operations, the acquisition      and disposal of assets and whatever may be substantial to the corporation’s      lines of strategic development”* |

3. The agreement relating to the Executive Committee of Gas Natural SDG, S.A., as contained in section c) of Agreement First of the Addendum dated December 16, 2002, is amended to read as follows:

|   | *“The Executive Committee of Gas Natural SDG, S.A., shall be composed of eight (8) members.*                                                                                                                                                                           |
|--------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|   |                                                                                                                                                                                                                                                                        |
|   | *“The parties to this Agreement shall vote at the meeting of the Board of Directors on the appointment of three (3) members of the Executive Committee from among the candidates proposed by Repsol YFP, S.A., another three (3) members from among those proposed by* |

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|   | *La Caixa, and the remaining two (2) from among independent Board members.  Among those proposed by La Caixa will be the President, who shall preside over the Executive Committee, and among those proposed by Repsol YFP, S.A., will be the Managing Director”* |
|--------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

IN WITNESS WHEREOF, and with the understanding that the contents of this Second Addendum shall be reported to the National Securities Market Commission, the parties affix their signatures hereto on two (2) copies on the date and at the place hereinbelow stated.

| LA CAIXA                              | REPSOL YPF, S.A.                            |
|---------------------------------------|---------------------------------------------|
|                                  |                                        |
|                                  |                                        |
|                                  |                                        |
| [signature] Antonio Brufau Niubó | [signature] Ramón Blanco Balín, |
| Barcelona, June 20, 2003              | Madrid, June 20, 2003                       |

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