By Geoffrey White
The Associated Press

CHICAGO - United Airlines, seeking $2.4 billion in yearly wage cuts to pacify lenders that have kept it flying in bankruptcy, took a step toward voiding its union labor contracts Friday.

The world's second-largest carrier filed a motion in U.S. Bankruptcy Court asking a judge to dissolve its labor agreements if the two sides are unable to agree on wage cuts, United spokesman Joe Hopkins said.

The carrier, however, offered to withdraw the motion until at least March 15 if four of its unions agreed to voluntary pay cuts and the court forced the other two, both Machinists groups, to forgo raises and take 13 percent cuts.

Rejection by Machinists-represented mechanics of proposed wage cuts was widely seen as the death blow to United's bid to avoid bankruptcy by getting a federal loan guarantee.

United argued that the wage concessions would allow it to meet cost-reduction benchmarks into the spring.

The Elk Grove Village, Ill.-based carrier used apocalyptic language in the motion, arguing that failure to meet its lenders' cost-reduction benchmarks "would spell the end for United."

Under United's proposal, the pilots union would take the biggest hit, having to give up scheduled raises and take 29 percent pay cuts.

United's branch of the Air Line Pilots Association remains committed to working with the company "to reach a rational business plan," spokesman Dave Kelly said late Friday.

Asked what a rational plan would be, Mr. Kelly replied: "Fair. A plan that does not punish the pilots for taking a leadership role."

Flight attendants would give up raises and take 9 percent cuts under United's proposal. Flight dispatchers and meteorologists would have to agree to 13 percent cuts.

All four unions would have to agree to the givebacks by Jan. 8.

Telephone calls to the two Machinists' unions were not returned.

United has until Feb. 15 to cut costs or it could lose the remainder of the $1.5 billion in interim financing a group of banks extended the carrier to allow it to restructure under Chapter 11 of the federal Bankruptcy Code.