By David Ingram and Diane Bartz

WASHINGTON (Reuters) - A federal judge on Friday set a tentative November 25 trial date in the U.S. government's legal challenge to an American Airlines <AAMRQA.UL> merger with U.S. Airways <LCC.N>.

Judge Colleen Kollar-Kotelly, who will try the case without a jury, announced the date at a hearing in U.S. District Court.

The U.S. Justice Department had asked for a March trial. The airlines had been pushing for November because holding a deal together for months puts a strain on the parties. During the merger review and challenge process, the companies say they are essentially in limbo, unable to merge but unable to make independent long-range plans.

"March 3, I think, is too far off. It needs to be a tighter, expedited schedule," the judge said in court.

The Justice Department filed a lawsuit in mid-August to block the deal, which would create the world's biggest air carrier. The government said the merger would lead to higher prices for customers, while the companies said it would make them more competitive and strengthen the market.

In its initial complaint, the department focused on Ronald Reagan National Airport, outside Washington, D.C., where the two companies control a combined 69 percent of takeoff and landing slots. It also listed more than 1,000 city pairs where the two airlines dominate the market.

Lawyers for the two sides said the trial was expected to last 10-12 business days. The judge will appoint a special master to help the discovery process move along faster. She set the next status conference for October 1.

The Justice Department plans to call about 15 witnesses and the airlines plan to call approximately six. The department proposes conducting depositions of as many as 50 people. The airlines said they want to depose about 10 people. Lawyers said they could exchange millions of documents.

The case at the U.S. District Court for the District of Columbia is No. 1:13-cv-012346-CKK.

(Writing by Howard Goller; Editing by Steve Orlofsky and Bernadette Baum)