DICK CHENEY’S chief of staff repeatedly lied to FBI agents and the grand jury investigating the CIA-leak scandal, the man who will prosecute him said last night.

Lewis “Scooter” Libby, the Vice-President’s closest aide, concocted a “compelling” but utterly untruthful account to disguise the fact that he blew the cover of the CIA official at the heart of the affair, Patrick Fitzgerald, the prosecutor who has led the 22-month investigation, said.

After handing down a five-count criminal indictment to Mr Libby for perjury and obstruction of justice for his role in the scandal, Mr Fitzgerald laid out the details of Mr Libby’s alleged dishonesty.

Mr Libby is the first senior White House official to face criminal charges in more than a century, and his trial promises to place Mr Cheney and the use of flawed intelligence to justify the Iraq war under a harsh spotlight. The maximum penalty of all five charges is 30 years in prison and a $1.25 million (£705,000) fine. Mr Libby said the indictments represented “a sad day for me and my family”, adding that he had complete confidence that he would be totally exonerated.

Although Mr Fitzgerald made clear that he had no plans to charge Mr Cheney with any crime, he said that one of Mr Libby’s biggest lies was to testify under oath that he learnt from journalists the identity of the CIA agent, Valerie Plame Instead, Mr Fitzgerald said, Mr Libby first learnt from Mr Cheney himself, on June 12, 2003, a month before she was “outed” in the press, that Ms Plame worked in the CIA’s Counterproliferation Division.

Mr Fitzgerald said that that information was classified, and that Mr Libby had an obligation not to leak it. Instead, he said, Mr Libby passed that information to three journalists in July 2003.

Referring to Ms Plame by her married name, Mr Fitzgerald said: “In July 2003 that fact that Valerie Wilson was a CIA officer was classified and not widely known outside the intelligence community. Her friends, neighbours and classmates had no idea she was a CIA officer.

But, he said, her “cover was blown” by Mr Libby. “When citizens testify before grand juries they are required to tell the truth,” Mr Fitzgerald said, “especially given that national security was at stake”.

He added: “Mr Libby lied about how and when he learnt and subsequently disclosed classified information about Valerie Wilson. He lied about it under oath, repeatedly.

“When the Vice-President’s chief of staff is charged with perjury and obstruction of justice, it shows all citizens are bound by the law.” According to Mr Libby’s testimony, he had been told by an NBC reporter that Ms Plame worked for the CIA.

Instead, Mr Fitzgerald said, Mr Libby had “multiple conversations” about Ms Plame before his conversation with the NBC reporter, including with Mr Cheney, Ari Fleischer, Mr Bush’s former spokesman, and “Official A”, a senior White House official who remained unidentified last night but who is believed to have been another key source in the leak.

Mr Fitzgerald was originally appointed in December 2003 to discover if Ms Plame had been deliberately exposed to punish her husband, Joseph Wilson, a former diplomat who in July 2003 accused the Bush Administration of “twisting” prewar intelligence to justify the invasion of Iraq.

In June 2002 Mr Wilson, on a CIA-sponsored trip set up by his wife, travelled to Niger to investigate reports that Iraq had tried to buy uranium there. He claimed in July 2003 that the White House ignored his report that he found no evidence of an Iraq/Niger link and implied that it had been Mr Cheney’s office that sent him to the West African nation.

A week later Robert Novak, a Conservative columnist, wrote that Mr Wilson had been sent to Niger by Ms Plame, the first time her name had been made public. The report caused a political storm after Mr Wilson claimed his wife was a covert CIA agent and that White House officials had leaked her identity as retribution.

Mr Fitzgerald made clear that Mr Libby had not committed the far more serious offence of “knowingly and intentionally outing a covert agent”.

He said that Mr Libby’s leaking of her CIA role was not being prosecuted. But Mr Libby appears to have fallen into the same trap that ensnared the Nixon Administration after the Watergate break-in and President Clinton after his affair with Monica Lewinsky: lying about the original act.

Democrats will try to turn the case into an examination of how the Bush Administration led the country into war. Harry Reid, the Democrat Senate Leader, said the indictments “suggest that a senior White House aide put politics ahead of our national security and the rule of law”.

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