Sen. Harry Reid, D-Nev., said Monday that he was joining a lawsuit against Vice President Dick Cheney to extract details of closed-door meetings with energy consultants that Reid suspects included conversations on a nuclear waste site in Nevada.

"There's no question that Vice President Cheney met on several occasions with nuclear power executives," Reid said. "Cheney needs to stop hiding the truth. He should tell the public which executives he met with, and when he met with them."

The General Accounting Office, Congress' investigative arm, filed a suit against the vice president on Friday seeking to force him to turn over notes from meetings of his National Energy Policy Group. The task force met several times last year before the president introduced his national energy policy nine months ago.

Several Enron executives were members of the task force, and some in Congress want to know if they tried to influence energy policy to help the embattled energy conglomerate, which declared the nation's largest-ever bankruptcy Dec. 2

The GAO originally wanted detailed minutes and records of Cheney's energy task force meetings. Now, the lawsuit says the GAO wants to know "who was present. ... whom the Vice President as ... and support staff met to gather information ... the date, purpose, agenda, and location of the meetings; how the vice president ... or others determined who would be invited; and the direct and indirect costs that were incurred."

The White House responded that it will fight the suit because the legislative branch does not have the authority to seek documents from the executive branch that could compromise the executive branch's ability to get good advice from consultants who fear everything they say will become public record.

"We have been ready to fight for this important principle since last August, when the GAO first indicated they were going to file a lawsuit," said White House spokesman Scott McClellan. "We look forward to the matter being reviewed by the courts."

Reid, the assistant majority leader in the Senate, is interested in finding out whether nuclear industry executives convinced Bush to support building Yucca Mountain, 90 miles northwest of Las Vegas, as a disposal site for the 77,000 tons of nuclear waste from the nation's 103 commercial nuclear power reactors.

Homeland Security Director Tom Ridge had warned the Bush administration that nuclear sites might be at risk of terrorist attack. One way to reduce the disaster of an attack would be to store the nuclear waste in a safe site.

But Reid argues that Yucca mountain is unsafe, despite 20 years and $7 billion in studies conducted by the Energy Department that found the site "scientifically and technically suitable" because of its remote location, arid conditions, and stable rock around the mountain.

The GAO wrote a briefing last year disagreeing with the Energy Department's conclusions and recommending the site be studied further before any decision is made.

Reid said Bush betrayed a campaign promise to not take action until scientifically sound evidence could determine the safety of the site.

"It's clear George W. Bush has flip-flopped on the issue, and I think these meetings had something to do with it," Reid added — toning down his earlier accusation that Bush lied.

Reid will file an amicus or "friend of the court" brief, which is usually filed by an individual or group not party to the litigation but seeking to support one side or the other. Reid's "friend of the court" brief will demand information relating to the secret energy documents and meetings.

The move was hailed by Rep. Shelley Berkley, D-Nev., and Democratic state Attorney General Frankie Sue Del Papa.

Leading Nevada Republicans — Gov. Kenny Guinn, Sen. John Ensign and Rep. Jim Gibbons — were hesitant or not immediately available for comment on joining the General Accounting Office lawsuit.

Greg Bortolin, Gov. Guinn's press secretary, said the GOP governor was in Washington, D.C. "At some point, the fight shifts to the Hill. I think this is one of those cases," Bortolin said.

Amy Spanbauer, spokeswoman for Rep. Gibbons, said Gibbons is adamantly opposed to Yucca Mountain but had not seen Reid's friend-of-the-court brief the senator expects to file this week.

Ensign spokeswoman Sari Mann had no immediate comment.

The suit is Walker v. Cheney.

Fox News' Carl Cameron and the Associated Press contributed to this report.