As the White House seeks to fend off attacks on President George W. Bush's service record, Washington is alive with talk that it is readying for another assault on its integrity: indictments from the CIA leak investigation.

For months, the investigation into who leaked the name of a CIA operative to the press seemed to have been buried in White House process and Justice Department discretion. Mr Bush had instructed his staff to co-operate with the investigation, but the questioning was conducted out of sight.

Phone records and e-mails were passed on through the office of the White House general counsel. Interviews were conducted, but not discussed.

Over the last 10 days, however, senior staff to the president and Vice-President Dick Cheney have filed in to give testimony to the grand jury. They include: Scott McClellan, the press secretary, Mary Matalin, Mr Cheney's former press secretary and now adviser to the Bush-Cheney '04 campaign, Claire Buchan, a deputy press secretary, and Adam Levine, who previously worked in the White House communications site.

There have also been "tip-offs" that indictments are in the offing. The names are circulating of senior staff in Mr Cheney's office.

Investigations into administration leaks to the press are notoriously hard to follow up. Since the name of the CIA agent - Valerie Plame - surfaced in Robert Novak's column last July, many have expected that the culprits would not be found. (Mr Novak said in his column he had spoken to two administration officials.) But the investigation is said to have gathered momentum, particularly since December when John Ashcroft, the attorney general, recused himself from the process and put Patrick Fitzgerald, a US attorney in Chicago, in charge of the inquiry.

If Mr Fitzgerald and his team of prosecutors generate indictments, however, it could add to the pressures on the White House.

Republicans have begun to speculate whether Mr Cheney is a liability. Deborah Pryce, Ohio congresswoman and chair of the House Republican Conference, said on Thursday that she had heard people talking about "his former association with Halliburton . . . guilt by association". But, speaking at a Christian Science Monitor breakfast, she added: "I think Dick Cheney can weather that easily."

For Mr Bush, the resurfacing criminal investigation comes as he tries to put an end to the questions of his military record.

Late on Wednesday night, the White House issued a facsimile of the president's dental records, intended to show that he had turned up for duty in Alabama just over 30 years ago, when he was a member of the National Guard.

The question about the president's military record long been whether he was awol in 1972, when he got transferred from the Texas Air National Guard to Alabama.

Payroll records show he did not do a day's service for over six months in 1972, when he was in Alabama. The dental records show that he did, however, show up on January 6 1973 at Dannelly air force base for a dental examination. Wesley Clark, the retired general who quit the Democratic presidential race, is expected today to endorse John Kerry, helping to fortify the front-runner status of the Massachusetts senator, Deborah McGregor writes in Washington.

Mr Clark, who ran a distant third in those races, is to make a formal endorsement of the Massachusetts senator at a campaign stop in Wisconsin, where the next big primary will be held on Tuesday.

© Copyright The Financial Times Ltd 2004.

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