WASHINGTON — Attorney General Eric Holder says American Airlines and US Airways must make broad concessions if they want to settle a lawsuit blocking their proposed merger.

Holder indicated Monday that the government’s concerns about the merger extend beyond the control that American and US Airways would have at Washington’s busy Reagan National Airport.

The attorney general’s comments show that the parties could try to reach a deal and avoid a Nov. 25 trial on the lawsuit, but also could indicate that the government’s demands may be too steep for the airlines.

The government sued to block the merger, which would create the world’s biggest airline, on grounds that it would restrict competition and drive up prices for consumers on hundreds of routes around the country.

At a press conference in Washington, Holder said his department has focused on forcing American and US Airways to make concessions at key busy airports throughout the United States.

Last week, American and US Airways began working on a settlement proposal that would include giving up valuable takeoff and landing rights at Reagan National, two people close to the situation told The Associated Press. It was not clear how many takeoff and landing slots the two airlines were willing to give up, and they did not want to make broader concessions.

This story was updated at 9:30 a.m., Nov. 5 to correct the name of the airline merging with US Airways.