Justice Department prosecutors, for the first time, yesterday said publicly that Rep. Richard Kelly (R-Fla.) took a $25,000 bribe in the FBI's Abscam undercover investigation.

Although Kelly hasn't been formally charged, the government laid out details of its investigation of him during U.S. District Court hearing in which William Rosenberg of Lynnbrook, N.Y., entered a guilty plea in connection with the case.

Rosenberg pleaded guilty to one count of conspiring to bribe a U.S. congressman (Kelly) and defraud the United States, and has agreed to cooperate in the Abscam investigation.

Soon after the first reports of the FBI's videotaped "sting" operation in early February, Kelly admitted taking the money. But he denied any wrongdoing, saying he accepted the cash as part of his own investigation of "shady characters" trying to buy immigration bills for wealthy Arab clients.

Kelly took $25,000 on Jan. 8, according to court papers in the Rosenberg case. Kelly said he kept the money in his car's glove compartment, and he eventually returned all but $174, which he said he had spent.

The charges against Rosenberg were handled by assisstant U.S. Attorneys Roger M. Adelman and Stephen R. Spivack. Adlelman told U.S. District Court Chief Judge William B. Bryant that Rosenberg was the first link in a chain of middlemen that led to Kelly during a search for members of Congress who would trade legislative favors for payoffs.

Stanley Weisz, a New York accountant, and Eugene Ciuzio, an acquaintance of Kelly in Florida, were the other links, according to the court papers. A federal grand jury here is expected to decide soon whether to formally charge Kelly and others.

Kelly's press spokesman, William Purvis, said the congresman was driving to Florida and could not be reched for comment.

But Purvis issued a statement saying "the action involving William Rosenberg does not contradict Congressman Kelly's previous remarks" that Kelly was involved only because he was conducting his own investigation.

"Congressman Kelly was not invloved in any conspiracy with William Rosenberg or anyone either to commit bribery or to defraud the government," the statement said.

Meanwhile, in New York, the Associated Press reported that the Justice Department has agreed to provide a House committee with grand jury materials from its Abscam probe, including videotapes of alleged payoffs involving five indicted congressmen.

The agreement is contained in an application filed yesterday in U.S. District Court in Brooklyn by E. Barrett Prettyman Jr., special counsel to the House Committee on Standards of Official Conduct.

A similar application for court approval of the agreement was being made here, the committee said.

The Justice Department had previously insisted that pertinent material be withheld from the committee until any criminal trials are held.

A hearing on the application was scheduled for next Friday before U.S. District Judge Jacob Mishler in Brooklyn.