The lawmakers also urged Bush to investigate the office of Vice President Dick Cheney, whose chief of staff, Lewis Libby, resigned on Friday and was indicted on perjury and other charges in connection with the probe.

Bush should take Cheney "to the woodshed" if necessary, a Democratic lawmaker said, and the Senate's top Democrat said Rove should be fired or quit.

"I think Karl Rove should step down," Senate Democratic leader Harry Reid of Nevada said on ABC's "This Week."

Mississippi Republican Sen. Trent Lott said the Bush administration needed "new blood, new energy, qualified staff," and that he expected the president to address his problems.

"I'm not talking about wholesale changes, but you've got to reach out and bring in more advice and counsel," Lott said on "Fox News Sunday."

Rove remains under investigation in the probe into who leaked the identity of covert CIA operative Valerie Plame, whose diplomat husband is a prominent Iraq war critic. The White House's credibility has been hurt by disclosures that Rove and Libby leaked Plame's identity, despite earlier official denials attributed to the two men.