L.A. Mayor Eric Garcetti met with President Obama last week during a trip to Washington. He was there to plead for federal funds for the L.A. River restoration project and the city's transit plans. Garcetti was an early Obama supporter, and has argued that his friendship with Obama could help win federal funding.

But friendship does not mean agreeing on everything. At the same time he is asking Obama for money, Garcetti is also publicly challenging the Obama administration over a major airline merger.

The Department of Justice sued in August to block the merger between American Airlines and U.S. Airways, which would create the world's largest airline. The antitrust suit argues that the merger would reduce competition and lead to increased fares.
In a letter released last week by the two airlines, Garcetti argued that the merger should be allowed to proceed.
“The creation of a new, robust, highly competitive, and improved airline will positively impact Los Angeles and other major hubs throughout the U.S.,” Garcetti wrote in the letter, which was addressed to Attorney General Eric Holder. “For these reasons, I ask for your reconsideration of the current lawsuit filed by the U.S. Department of Justice against the merger.”
Getting Garcetti to go on record against his friends in the Obama administration counts as a big win for John Ek, American Airlines' lobbyist at City Hall. According to emails reviewed by the L.A. Weekly, Ek's firm has been lobbying Garcetti's office to come out in favor of the merger since August.
The mayors of seven other cities previously expressed support of the merger. According to the emails, Ek's firm was working in August to put Garcetti in touch with Philadelphia Mayor Michael Nutter, who is a key supporter of the deal.
The other mayors, including Nutter and Chicago Mayor Rahm Emanuel, a former Obama chief of staff, signed a letter last week that was much harsher on the Obama administration. That letter called the antitrust action an “ill-conceived lawsuit,” and asserted that “the health and well-being of our cities and our citizens depends on this combination moving forward.”
Garcetti's tone was gentler. He enumerated the economic benefits from the merger, but avoided criticizing Holder.
Asked why Garcetti did not sign on to the harsher letter, Garcetti spokesman Jeff Millman said “We thought our letter was very impactful.”

Holder American US Air Airline Merger Support October 2013.pdf

LA Weekly