Exhibit 7.1

PETROLEOS MEXICANOS SUBSIDIARY ENTITIES AND SUBSIDIARY COMPANIES

Computation of ratio of earnings to fixed charges

(In thousands of Mexican pesos)



|                                                                             |  |      |              |   |      |  |             |      |  |  |              |  
|---------------------------------------------------------------------------- |  | ---- | ------------ | - | ---- |  | ----------- | ---- |  |  | ------------ | -
|                                                                             |  | 2013 |              |   | 2012 |  |             | 2011 | 
|IFRS                                                                         |  |      |              |   |      |  |             |      |  |  |              |  
|Fixed Charges(1):                                                            |  |      |              |   |      |  |             |      |  |  |              |  
|Interest capitalized in fixed assets                                         |  |      | 2,943,597    |   |      |  | 2,110,075   |      |  |  | 4,292,351    |  
|Interest expense                                                             |  |      | 54,067,022   |   |      |  | 72,951,202  |      |  |  | 63,003,854   |  
|                                                                             |  |      |              |   |      |  |             |      |  |  |              |  
|Total interest cost                                                          |  |      | 57,010,618   |   |      |  | 75,061,277  |      |  |  | 67,296,206   |  
|Total Fixed Charges                                                          |  |      | 57,010,618   |   |      |  | 75,061,277  |      |  |  | 67,296,206   |  
|                                                                             |  |      |              |   |      |  |             |      |  |  |              |  
|Net income (loss)                                                            |  |      | (170,058,427 | ) |      |  | 2,600,478   |      |  |  | (106,942,256 | )
|Hydrocarbon Income Tax (IRP)                                                 |  |      | 3,787,543    |   |      |  | 2,442,280   |      |  |  | (677,392     | )
|Income Tax and Others                                                        |  |      | 3,672,466    |   |      |  | 2,138,856   |      |  |  | 3,853,408    |  
|Profit sharing in subsidiaries and affiliates (income from equity investees) |  |      | 706,710      |   |      |  | 4,797,607   |      |  |  | (810,752     | )
|                                                                             |  |      |              |   |      |  |             |      |  |  |              |  
|Pretax income from continuing operations before income from equity investees |  |      | (161,891,708 | ) |      |  | 11,979,221  |      |  |  | (104,576,991 | )
|Fixed Charges(1):                                                            |  |      | 57,010,618   |   |      |  | 75,061,277  |      |  |  | 67,296,206   |  
|Amortization of interest capitalized                                         |  |      | 117,744      |   |      |  | 84,403      |      |  |  | 171,694      |  
|Dividends received on investments in shares                                  |  |      | 914,116      |   |      |  | 685,704     |      |  |  | 599,907      |  
|Interest capitalized in fixed assets                                         |  |      | (2,943,597   | ) |      |  | (2,110,075  | )    |  |  | (4,292,351   | )
|                                                                             |  |      |              |   |      |  |             |      |  |  |              |  
|Earnings                                                                     |  |      | (106,792,827 | ) |      |  | 85,700,530  |      |  |  | (40,801,536  | )
|                                                                             |  |      |              |   |      |  |             |      |  |  |              |  
|Amount by which fixed charges exceed earnings                                |  |      | 163,803,445  |   |      |  | (10,639,253 | )    |  |  | 108,097,741  |  
|Ratio of earnings to fixed charges                                           |  |      | (1.87        | ) |      |  | 1.14        |      |  |  | (0.61        | )



|(1) | These figures do not include rental expense.
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