Defense Secretary Richard B. Cheney escalated a bitter budget confrontation with House Democrats yesterday by announcing that he would impose his solution for making up a $780 million military pay shortage if he cannot reach agreement with Congress when it returns in June.

Even before Cheney's surprise announcement, the impasse had threatened to sour relations between the secretary and the Democrats just as the key defense committees in Congress are preparing to draft a fiscal 1991 defense budget that will contain the deepest cuts in years.

"It's an ominous sign for the future," said Rep. Norman D. Dicks (D-Wash.), an influential member of the House Appropriations Committee. "There's got to be some comity between the players."

Congress adjourned for an 11-day Memorial Day recess late Thursday amid recriminations and without an agreement on how to make up the pay shortfall, which resulted from automatic cuts imposed last fall by the Gramm-Rudman-Hollings deficit reduction law.

To cover the shortfall and forestall thousands of early retirements by Oct. 1, Cheney has proposed shifting funds from a selective list of programs that the Defense Department has drawn up.

But House Armed Services Committee Chairman Les Aspin (D-Wis.) has insisted that some $230 million of the funds be shifted out of Cheney's top priority strategic programs, including the B-2 bomber, Strategic Defense Initiative, MX rail garrison missile and SSN-21 submarine. House Democrats, rallying behind Aspin, reportedly have proposed billing the B-2 program $80 million.

Under a long-standing agreement with Congress, the Defense Department seeks approval of the four main House and Senate defense panels before shifting funds in the Pentagon budget. But several congressional sources said yesterday that the defense secretary has legal authority to move the funds, overruling the objections of committee chairmen such as Aspin.

As it became clear Thursday that Aspin would not back down, he came under sharp attack from Republicans. House Minority Whip Newt Gingrich (R-Ga.) said it was "outrageous that the men and women in uniform and their families would be used as a hostage by the Democratic chairman of the Committee on Armed Services." Rep. Joseph M. McDade (R-Pa.), ranking Republican on the Appropriations Committee, accused Aspin of exercising a "pocket veto."

One source said there was "a lot of ill will" on both sides, and a "we're going to break Aspin mood" at the Pentagon.

However, the chairman's position was bolstered Thursday by support from influential pro-defense Democrats, including Dicks, and Reps. G.V. "Sonny" Montgomery (D-Miss.), Beverly B. Byron (D-Md.) and Norman Sisisky (D-Va.), of the House Armed Services Committee.

Aspin stressed yesterday that he wants to solve the pay problem quickly. But he said Pentagon "reprogramming" proposals offered since January have been crafted to soften the impact of the automatic Gramm-Rudman-Hollings cuts that other parts of the government have had to accept because they did not shift funds out of key weapons programs supported by Cheney.

"I want to raise the noise level on this so that the Pentagon never tries to do this again," he said.

Cheney's announcement yesterday also threw into limbo the status of $648 million urgently needed by the Defense Department to cover a similar shortfall in the military medical and health accounts. On Thursday, Aspin joined the Senate Armed Services Committee and the House and Senate Appropriations defense subcommittees in approving a Pentagon funding shift to cover the shortage.

But Cheney said he would not free up those funds until the pay problem was also solved.