A four-hour-long filibuster that divided the Senate leadership and threatened to disrupt the final four days of the legislative session ended early this morning when members of the black caucus agreed to stop trying to block passage of a sweeping bank and credit deregulation bill in return for a meeting with Gov. Harry Hughes today.

The five-member caucus began filibustering the banking measure Thursday evening, saying that banks in Maryland had been unfair to minorities. The bill, which would eliminate many restrictions on financial institutions and permit a variety of new fees to be charged against consumers, had already passed easily in the Senate, but was returned there for its concurrence on amendments approved by the House of Delegates.

The filibuster was led by Sen. Clarence W. Mitchell (D-Baltimore), who had said he would try to talk the bill to death. Mitchell was joined by his four black colleagues, including majority leader Clarence W. Blount.

As the filibuster continued, Senate President Melvin A. Steinberg talked of stripping Blount and Mitchell, who is a committee chairman, of their leadership posts. "To obstruct the business of the Senate this late in the session is irresponsible," Steinberg told a reporter in a hallway outside the Senate Chamber. "As far as I'm concerned all bets are off with those guys. I don't believe in blackmail."

Shortly before midnight, the caucus members went into a closed-door meeting with Steinberg that lasted for almost an hour. When they emerged, a deal had been made: The members would stop the filibuster and Steinberg would call the governor on their behalf and arrange a meeting with Hughes and banking leaders in the morning. Hughes had said yesterday that he intends to sign the banking bill.

The black leaders said they want a public expression by the governor and the bankers that they will try to do more to help minorities in Maryland. "There is little question that the banks have gone backwards in terms of affirmative action for minorities in the last few years," Mitchell said. "We want some assurances this will stop. After the meeting we will end the filibuster regardless of what is said."

The only problem with the agreement arose when a Steinberg aide was told by a state trooper answering the phone at the governor's mansion that Hughes was asleep and could not be disturbed.

"What should I do if the state is being attacked, call the president?" said Steinberg, who was coping with the third Senate filibuster in a week. Finally, Hughes' Chief-of-Staff Ejner J. Johnson was reached and the meeting was arranged for this morning.

Steinberg said there would be no changes in his leadership. "I said those things in the heat of battle," he said. Mitchell added: "We kissed and made up."