Exhibit 10.3



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|---- |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|LOGO |  | (1 of 2) 
PRESIDENT ROBERT C. BARG
 VICE
PRESIDENTS ALLEN E. EVANS, JR.
RANDOLPH K. GREEN JOHN G. HATTNER C. H. (SCOTT)
REES III DANNY S. SIMMONS
DAN PAUL SMITH THOMAS M. SOUERS

April 26, 2013

Mtro. Emilio R. Lozoya Austin

Director General

Petróleos Mexicanos

Avenida Marina
Nacional No. 329

Colonia Petróleos Mexicanos C.P. 11311

México

Dear Mtro. Lozoya Austin:

We hereby consent to all references to our firm as set forth in the Annual Report on Form 20-F of Petróleos Mexicanos for the year
ending December 31, 2012, (the Form 20-F), under the heading Exploration and Production (Reserves), and to the filing of our audit letter dated February 22, 2013, as an exhibit to the Form 20-F. We have audited the
estimates of proved oil, condensate, natural gas and oil equivalent reserves owned by the United Mexican States (Mexico) as of January 1, 2013, for 28 fields located offshore Mexico in the Northeastern Marine Region. These estimates
were prepared by Pemex-Exploración y Producción in accordance with the reserves definitions of Regulation S-X Rule 4-10(a) of the U.S. Securities and Exchange Commission.



Sincerely, 
NETHERLAND, SEWELL INTERNATIONAL, S. DE R.L. DE C.V.By:

LOGORobert C. Barg, P.E.
President


1601 ELM STREET. SUITE 4500 - DALLAS,
TEXAS 75201-4754  PH 214-969-5401 -FAX 214-969-5411



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Exhibit 10.3



|     |  |                                                                                                                                                                                   
|---- |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|LOGO |  | (2 of 2) 
PRESIDENT- ROBERT C. BARG
 VICE
PRESIDENTS ALLEN E. EVANS, JR.
RANDOLPH K. GREEN JOHN G. HATTNER C. H. (SCOTT)
REES III DANNY S. SIMMONS
DAN PAUL SMITH THOMAS M. SOUERS

April 26, 2013

Mtro. Emilio R. Lozoya Austin

Director General

Petróleos Mexicanos

Avenida Marina
Nacional No. 329

Colonia Petróleos Mexicanos C.P. 11311

México

Dear Mtro. Lozoya Austin:

We hereby consent to all references to our firm as set forth in the Annual Report on Form 20-F of Petróleos Mexicanos for the year
ending December 31, 2012, (the Form 20-F), under the heading Exploration and Production (Reserves), and to the filing of our audit letter dated February 22, 2013, as an exhibit to the Form 20-F. We have audited the
estimates of proved oil, condensate, natural gas and oil equivalent reserves owned by the United Mexican States (Mexico) as of January 1, 2013, for 108 fields located onshore Mexico in the Southern Region. These estimates were
prepared by Pemex-Exploración y Producción in accordance with the reserves definitions of Regulation S-X Rule 4-10(a) of the U.S. Securities and Exchange Commission.



Sincerely, 
NETHERLAND, SEWELL INTERNATIONAL, S. DE R.L. DE C.V.By:

LOGORobert C. Barg, P.E.
President


1601 ELM STREET, SUITE 4500 
DALLAS, TEXAS 75201-4754  PH: 214-969-5401  FAX: 214-969-5411