By David Shepardson

WASHINGTON (Reuters) -U.S. Transportation Secretary Pete Buttigieg on Monday said he told Mexican President Andres Manuel Lopez Obrador last week any decision to reinstate the country's air safety rating would not be based on politics.

"The rating as I emphasized to the president is a safety decision. It's independent of any economic, commercial or political consideration, but I did assure him that there would not be any unnecessary or improper delay in processing that," Buttigieg told Reuters on the sidelines of an event in Washington.

The U.S. Federal Aviation Administration (FAA) downgraded Mexico to Category 2 in May 2021, citing safety deficiencies and restricting the ability of Mexican airlines to open new routes to the United States.

After the meeting on Wednesday, Lopez Obrador said the U.S. and Mexico still have "differences" of opinion regarding Mexico's recovery of a coveted air safety rating. He said the U.S. was "bargaining" with Mexico over the rating and that a change to cargo flights was another sticking point between the countries.

Lopez Obrador wants cargo flights to land at the new Felipe Angeles airport in Mexico City rather than the more centrally located Benito Juarez airport to free up space, but said some U.S. carriers are reluctant to move

Buttigieg raised concerns about the timing of the cargo move in his meeting.

"From the perspective of our cargo carriers, it is very important to get some of that flexibility for the move and I really appreciate the (Mexican) president's willingness to extend the timeline," Buttigieg said on Monday.

The FAA recently wrapped up one of a series of audits on Mexico. Mexican Transportation Minister Jorge Nuno on Wednesday had said the audit was Mexico's "last", implying a positive resolution.

Mexico has revamped compliance with international standards on licensing, aircraft operations and airworthiness of craft, among other things.

(Reporting by David ShepardsonEditing by Bill Berkrot)