Superpower leaders may be reaching historic arms control accords in Washington this week, but congressional and Pentagon leaders cannot seem to resolve a bitter fight over pay and benefits affecting thousands of military enlisted and officers.

One congressional aide calls it a "policy shootout." A member of Congress involved in the dispute says it is more down and dirty: "We can't believe this fight is taking place between two former colleagues."

The two former colleagues are House Armed Services Committee Chairman Les Aspin (D-Wis.) and Defense Secretary Richard B. Cheney, former member of Congress.

"Cheney's being stubborn," Aspin groused yesterday.

"He's the holdout -- not us," said Cheney's chief spokesman, Pete Williams.Quintessential Battle

It has escalated into one of those quintessential Washington battles that can tie bureaucracies in knots for months -- and also a matter that escalates into a question of political pride.

The debate began over a $1.4 billion budget shortfall the Pentagon says it must recover to avert thousands of forced early retirements, wide-ranging freezes on promotions and delays in medical payments for hundreds of thousands of military personnel.

As they do every year when bank accounts are overdrawn, Defense Department officials marched to Capitol Hill seeking the usually routine permission to shift money from other accounts to make up the shortage. In government jargon, the process is called "reprogramming."

All it takes to keep those pay checks and medical benefits coming is approval from four congressional committees.

This year three agreed, but the chairman of the fourth -- Aspin -- balked, complaining that Cheney was using the system to protect pet weapons programs from the Gramm-Rudman-Hollings deficit cuts at the expense of personnel programs.

Aspin has insisted that some of the money needed for personnel accounts be withdrawn from strategic programs, such as the B-2 "stealth" bomber.

Cheney has denied that he has tried to abuse the system, saying he has merely followed the same path of other defense chiefs who routinely ask Congress for extra help in funding personnel programs later in the budget year.

"The question is where the dough ought to come from," Williams said. "No member wants to see it come out of his sacred programs. Aspin is on no loftier ground than any of the rest.

"This is not Dick Cheney versus Les Aspin," Williams added. "There is a package on which the Defense Department and seven committee chairmen and ranking Republicans agree. Aspin doesn't want to sign off."

But as the February fight drags into the summer, the Navy's medical and health accounts have gone broke and the service stopped reimbursing doctors and patients for medical payments on May 8.

Aspin's colleagues have begun making other dire predictions. His counterpart on the Senate Armed Services Committee, Sam Nunn (D-Ga.), warned that if the problem is not resolved, the military may have to fire 40,000 active-duty personnel, freeze promotions for another 50,000 and cut the number of new recruits by 90,000.

Last week Cheney warned that if no compromise is reached soon after Congress returns next week from its Memorial Day recess, he will impose his solutions, using procedures that do not require congressional approval. Small Breakthrough

A small breakthrough came this week, however, prompted by the Navy's lack of funding for CHAMPUS -- Civilian Health and Medical Program of the Uniformed Services. Cheney had opposed separating the CHAMPUS problem -- a $648 million shortfall -- from the personnel account debt of about $800 million.

Members of Congress, who were being inundated by letters and telephone calls from anxious sailors and doctors who treat sailors, applied the heat. "I was pleading on bended knee for a release of CHAMPUS funds," said Sen. John W. Warner (R-Va.).

Sen. John Glenn (D-Ohio) considered even more drastic action, according to officials involved in the fray. He threatened to fly a planeload of angry sailors and their families from naval bases to the Capitol for a boisterous hearing before the Senate Armed Services Committee.

To break this impasse, Cheney agreed to allow the Navy to temporarily move some money within its operations and maintenance account to cover the $75 million shortfall in the insurance program. The Air Force and Army would have the same authority if their insurance accounts run dry as expected in the next few weeks, according to Pentagon officials.

Meanwhile, Cheney is expected to meet with House Speaker Thomas S. Foley (D-Wash.) next week to continue negotiations.

"I don't have any bottom-line numbers on what it would take in order for me to agree," Aspin said. "There's got to be some agreement on the degree of pain."