WASHINGTON - House Democrats were working yesterday to avert a showdown with President Obama over who in Congress should receive sensitive information on the CIA's covert activities.

House Speaker Nancy Pelosi (D., Calif.) said Rep. Silvestre Reyes (D., Texas), chairman of the House Permanent Select Committee on Intelligence, was negotiating with administration officials over a measure to enlarge the number of lawmakers who receive CIA briefings from the eight leading members of Congress to all members of the House and Senate intelligence committees.

Obama vowed Wednesday to veto the pending Intelligence Authorization Bill if it contained language expanding the briefings beyond the so-called Gang of Eight - the Democratic and Republican leaders of both houses of Congress, and heads and ranking members of the two intelligence committees.

The bill was scheduled for a vote last night, but it wasn't clear there would be a vote.

The White House said giving all intelligence panel members access to the CIA's covert work "would run afoul of tradition by restricting an important established means by which the president protects the most sensitive intelligence activities that are carried out in the national security interests."

The House drive to change the briefing rules stems from complaints from lawmakers that they had not received all the information they should have from President George W. Bush's administration.

Complaints about incomplete or misleading intelligence information reached a boiling point in May, when Pelosi said the CIA did not tell her in a 2002 briefing that it had used waterboarding against a terrorism suspect.

House Intelligence Committee Democrats created a new flap Wednesday when they accused the CIA of misleading or lying to Congress for the last eight years, in essence bolstering Pelosi's claim.

They based their accusations, outlined in letters released this week, on a closed-door briefing that CIA Director Leon Panetta gave to the committee on June 24.

"Top CIA officials have concealed significant actions from all members of Congress and misled members for a number of years from 2001 to this week," Democratic panel members wrote to Panetta on June 26, summarizing his briefing. "This is similar to other deceptions of which we are aware from other recent periods."

Panetta said in the briefing that House members had not been fully informed about one classified program at the CIA, according to an official familiar with the matter, the Associated Press reported.

The program was begun after the Sept. 11 attacks and brought to Panetta's attention a day before his June 24 testimony by an office within the spy agency, the official said.

Panetta asked a senior officer to find ways to keep Congress better informed, the official said.

"This agency and this director believe it is vital to keep the Congress fully and currently informed. Director Panetta's actions back that up," CIA spokesman George Little said in a statment.

Congressional Republican leaders also rejected the Democrats' accusations.

"I do not believe that the CIA lied to Congress," House Minority Leader John A. Boehner said. "I'm still waiting for Speaker Pelosi to either put up the facts or retract her statement and apologize."

California Republican Rep. Darrell Issa, a former Intelligence Committee member, urged FBI Director Robert Mueller to investigate "whether the CIA director's communications to members of Congress and statements have been fully accurate."