Exhibit 23.6
(Part 1of 3)
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September 19, 2017
Dr. José Antonio González Anaya
Director General
Petróleos Mexicanos
Avenida Marina Nacional No. 329
Torre Ejecutiva, Piso 44
Colonia Verónica Anzures
11300 Ciudad de México
México
Dear Dr. González Anaya:
We hereby consent to (a) all references to our firm as set forth under the heading “Experts” in the Registration Statement onForm F-4 filed by Petróleos Mexicanos (the “FormF-4”); (b) all references to our firm as set forth under the heading “Item 4—Information on the Company—Business Overview—Exploration and Production—Reserves” in the Annual Report onForm 20-F of Petróleos Mexicanos for the year ended December 31, 2016 (the “Form20-F”); and (c) the incorporation by reference in the FormF-4 of our audit letter describing our review of the estimates of Petróleos Mexicanos’ proved oil, condensate, plant liquids, dry gas, and oil equivalent reserves as of January 1, 2017, for 72 fields located in Poza Rica-Altamira District in the North Region of Mexico, which audit letter was originally filed as Exhibit 10.4 to theForm 20-F. The estimates included in our report were prepared in accordance with the reserves definitions of RegulationS-X Rule4-10(a) of the U.S. Securities and Exchange Commission.
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Sincerely, |
|
NETHERLAND, SEWELL INTERNATIONAL, S. DE R.L. DE C.V. |
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By: | | /s/ ROBERT C. BARG |
| | Robert C. Barg, P.E. |
| | President |
RCB:DCC
2100 ROSS AVENUE, SUITE 2200 ● DALLAS, TEXAS 75201-2737 ● PH 214-969-5401 ● FAX 214-969-5411
Exhibit 23.6
(Part 2 of 3)

September 19, 2017
Dr. José Antonio González Anaya
Director General
Petróleos Mexicanos
Avenida Marina Nacional No. 329
Torre Ejecutiva, Piso 44
Colonia Verónica Anzures
11300 Ciudad de México
México
Dear Dr. González Anaya:
We hereby consent to (a) all references to our firm as set forth under the heading “Experts” in the Registration Statement onForm F-4 filed by Petróleos Mexicanos (the “FormF-4”); (b) all references to our firm as set forth under the heading “Item 4—Information on the Company—Business Overview—Exploration and Production—Reserves” in the Annual Report onForm 20-F of Petróleos Mexicanos for the year ended December 31, 2016 (the “Form20-F”); and (c) the incorporation by reference in theForm F-4 of our audit letter describing our review of the estimates of Petróleos Mexicanos’ proved oil, condensate, plant liquids, dry gas, and oil equivalent reserves as of January 1, 2017, for 26 fields located in the Litoral de Tabasco District in the Southwest Marine Region of Mexico, which audit letter was originally filed as Exhibit 10.4 to theForm 20-F. The estimates included in our report were prepared in accordance with the reserves definitions of RegulationS-X Rule4-10(a) of the U.S. Securities and Exchange Commission.
| | |
Sincerely, |
|
NETHERLAND, SEWELL INTERNATIONAL, S. DE R.L. DE C.V. |
| |
By: | | /s/ ROBERT C. BARG |
| | Robert C. Barg, P.E. |
| | President |
RCB:DCC
2100 ROSS AVENUE, SUITE 2200 ● DALLAS, TEXAS 75201-2737 ● PH 214-969-5401 ● FAX 214-969-5411
Exhibit 23.6
(Part 3 of 3)

September 19, 2017
Dr. José Antonio González Anaya
Director General
Petróleos Mexicanos
Avenida Marina Nacional No. 329
Torre Ejecutiva, Piso 44
Colonia Verónica Anzures
11300 Ciudad de México
México
Dear Dr. González Anaya:
We hereby consent to (a) all references to our firm as set forth under the heading “Experts” in the Registration Statement on FormF-4 filed by Petróleos Mexicanos (the “FormF-4”); (b) all references to our firm as set forth under the heading “Item 4—Information on the Company—Business Overview—Exploration and Production—Reserves” in the Annual Report onForm 20-F of Petróleos Mexicanos for the year ended December 31, 2016 (the “Form20-F”); and (c) the incorporation by reference in theForm F-4 of our audit letter describing our review of the estimates of Petróleos Mexicanos’ proved oil, condensate, plant liquids, dry gas, and oil equivalent reserves as of January 1, 2017, for 27 fields located in the Aceite Terciario del Golfo District in Veracruz in the Southeast Marine Region of Mexico, which audit letter was originally filed as Exhibit 10.4 to theForm 20-F. The estimates included in our report were prepared in accordance with the reserves definitions of RegulationS-X Rule4-10(a) of the U.S. Securities and Exchange Commission.
| | |
Sincerely, |
|
NETHERLAND, SEWELL INTERNATIONAL, S. DE R.L. DE C.V. |
| |
By: | | /s/ ROBERT C. BARG |
| | Robert C. Barg, P.E. |
| | President |
RCB:DCC
2100 ROSS AVENUE, SUITE 2200 ● DALLAS, TEXAS 75201-2737 ● PH 214-969-5401 ● FAX 214-969-5411