WASHINGTON — Rep. Vito Fossella is expected to announce as early as today whether he plans to seek re-election — or even stay in office — following an arrest on drunken driving charges and his disclosure last week that he had an affair and an out-of-wedlock child.

The Republican of Staten Island was with his family yesterday, and party sources were downplaying reports that he was leaning toward trying to mount a bid for another term.

“He hasn’t made a decision,” a spokeswoman for the congressman, Susan Del Percio, said yesterday.

An effort by Mr. Fossella to run for a sixth full term this fall would put the national party in a jam. With Republicans already likely to lose seats in Congress this fall, leaders in Washington desperately want to retain the seat in New York’s 13th congressional district, and they have made little secret in recent days that they want Mr. Fossella to step aside.

A spokesman for the Staten Island district attorney, Daniel Donovan, confirmed yesterday that the House Republican leader, Rep. John Boehner, and the chairman of the party’s congressional campaign committee, Rep. Tom Cole, had called on Friday to gauge Mr. Donovan’s interest in a run for Mr. Fossella’s seat.

“They said if Dan was interested in running, they’d be interested in having him,” the spokesman, William Smith, said, adding that the leaders also promised plenty of resources for Mr. Donovan to wage a competitive campaign.

Yet Mr. Donovan’s candidacy is predicated on Mr. Fossella’s choosing either to resign or not run again this fall. The district attorney is not expected to challenge him in a primary if he seeks re-election.

Mr. Fossella could face a mandatory five days in jail following his May 1 drunken driving arrest, and he acknowledged last week that he had fathered a daughter with a former Air Force officer, Laura Fay, with whom he had an affair.

Mr. Boehner told reporters on Thursday that Mr. Fossella “is going to have some decisions to make over the weekend” — a statement that was taken by many as an ultimatum by the party leadership that Mr. Fossella make his intentions known by today.

Upset by the leader’s comment, Mr. Fossella and Rep. Peter King of Long Island, a close friend of Mr. Fossella’s in the House, sought out Mr. Boehner on the House floor on Thursday afternoon. Mr. Boehner told them his comments had been misconstrued and that Mr. Fossella was under “no pressure” to decide this weekend, Mr. King said in an interview yesterday, indicating that an announcement from Mr. Fossella may not come immediately.

“The world is not going to end if Vito takes an extra few days,” Mr. King said. “People in his own party should step back and give him some breathing room.”