Updated

Vice President Joe Biden, well-known for his verbal gaffes, may have finally outdone himself, divulging potentially classified information meant to save the life of a sitting vice president.

According to a report, while recently attending the Gridiron Club dinner in Washington, an annual event where powerful politicians and media elite get a chance to cozy up to one another, Biden told his dinnermates about the existence of a secret bunker under the old U.S. Naval Observatory, which is now the home of the vice president.

The bunker is believed to be the secure, undisclosed location former Vice President Dick Cheney remained under protection in secret after the 9/11 attacks.

Eleanor Clift, Newsweek magazine's Washington contributing editor, said Biden revealed the location while filling in for President Obama at the dinner, who, along with Grover Cleveland, is the only president to skip the gathering.

According to Clift's report on the Newsweek blog, Biden "said a young naval officer giving him a tour of the residence showed him the hideaway, which is behind a massive steel door secured by an elaborate lock with a narrow connecting hallway lined with shelves filled with communications equipment."

Clift continued: "The officer explained that when Cheney was in lock down, this was where his most trusted aides were stationed, an image that Biden conveyed in a way that suggested we shouldn't be surprised that the policies that emerged were off the wall."

On Monday, Biden's press office issued a statement in response to this story, denying the bunker report.

"What the Vice President described in his comments was not -- as some press reports have suggested -- an underground facility, but rather, an upstairs workspace in the residence, which he understood was frequently used by Vice President Cheney and his aides," said Biden's spokesperson Elizabeth Alexander. "That workspace was converted into an upstairs guestroom when the Bidens moved into the residence. There was no disclosure of classified information."

In December 2002, neighbors complained of loud construction work being done at the Naval Observatory, which has been used as a residence by vice presidents since 1974.

The upset neighbors were sent a letter by the observatory's superintendent, calling the work "sensitive in nature" and "classified" and that it was urgent it be completed "on a highly accelerated schedule."

Residents said they believed workers were digging deep into the ground, which would support Biden's report of a secret bunker, but officials never confirmed the purpose of the work performed.

The revelation is the latest from Biden, who has a long history of political blunders.

Most recently, he said in a televised interview that if a family member asked him about traveling he'd advise staying away from public transportation or confined spaces to avoid swine flu -- a remark described as "borderline fearmongering" by an airline spokesman.

Click to see a full list of Biden's political blunders