Dinner parties buzzed with a tale that had the President cowering in a corner of their sitting room in the White House after the vase, a valuable piece of government furniture, whizzed past his ear and smashed against a wall. Mrs Clinton shrugged it off as a malicious rumour.

But an FBI agent who was working at the White House at the time has come forward to link the alleged vase-tossing to the current furore about why Clinton officials ordered up 339 FBI background files on Republicans three years ago.

Gary Aldrich, now retired, said in the Wall Street Journal that "outrageous" requests for FBI information were made, some designed to "harass" staff whose loyalty to the President and his wife was in question.

Mr Aldrich said: "What prompted the White House to investigate these staffers was a story, leaked to the press, that Mrs Clinton had thrown a lamp at the President during a domestic argument. The Clintons had to know who the leaker was. Result: decent, loyal, law-abiding citizens with spotless records were investigated by the FBI again."

Republicans on the Whitewater Committee plan to mention allegedly "highly improper conduct"

The Senate Whitewater investigators, who plan to issue a report of their 14-month inquiry on Monday night, have suddenly homed in on new questions about Mrs Clinton's testimony that she had no idea why records of her work on a land deal were missing for a year and then suddenly turned up at her White House quarters.

Whatever happens, Monday is likely to be embarrassing for the White House.

Republicans on the Whitewater Committee plan to mention allegedly "highly improper conduct". There is talk of possible perjury charges against Maggie Williams, Mrs Clinton's chief-of-staff, and her closest confidante, Susan Thomases.

The suspicion is that they may have lied about what was said in phone calls to Mrs Clinton on the night in 1993 when Vincent Foster, the White House counsel, was found shot dead.

Monday is also the opening of a trial in Little Rock, Arkansas, of two bankers at which Mr Clinton will have to offer videotaped evidence.

This report appeared in Saturday's edition of The Daily Telegraph