Mesa Air Group Inc.'s disputed agreement to supply and fly planes for Delta Air Lines Inc. will come to trial in bankruptcy court in New York in July.

U.S. Bankruptcy Judge Martin Glenn said yesterday in New York that his bankruptcy court will decide whether the Mesa and Delta code-share agreement will continue. Mesa's Freedom Airlines subsidiary flies routes booked by Delta.

A trial is scheduled for July 12 in Manhattan. Mesa wanted Glenn to approve a motion yesterday that would maintain the agreement.

“;There has not been progress on the underlying substance”; of the issue, despite some talks between Mesa's and Delta's lawyers, Laura Davis Jones, an attorney for Mesa, told the judge.

Mesa, which is the parent company of interisland carrier go!, sued Delta in 2008 in federal court in Georgia after Delta terminated their agreement. Delta said Mesa defaulted on the contract by not completing a required percentage of flights each month. Mesa said in its lawsuit that Delta changed the terms for calculating the percentage so it could end the contract and reduce costs and reliance on regional carriers.

In July, a federal appeals court upheld an order that prevented Delta from canceling the agreement and returned the case to the Georgia court.

Lawyers told Glenn yesterday they would try to persuade U.S. District Judge Clarence Cooper in Atlanta to reach a decision on the breach of contract lawsuit as soon as possible.

Under the agreement, signed in 2005 and expiring in 2012, Delta sets the schedules and Mesa supplies, flies and maintains the planes. In a Jan. 26 letter to Glenn, Mesa's lawyers said the outcome of the code-share plan would affect the company's decision whether to assume or reject leases for about 22 aircraft, representing 17 percent of its fleet.

Mesa, based in Phoenix, filed for Chapter 11 reorganization last month, listing assets of $975.5 million and debt of $868.6 million. The company said at the time bankruptcy protection would “;allow us to eliminate excess aircraft.”;

Last month Glenn granted Mesa authority to give back 20 planes to Raytheon Aircraft Credit Corp.

Mesa alleged that Delta approached it in 2008 to buy out the code-sharing contract and then terminated the deal after terms couldn't be reached.