A report that President Clinton and a former White House intern, Ms Monica Lewinsky, were discovered alone together several times in the private quarters of the White House is being investigated by the independent counsel, Mr Kenneth Starr.
ABC News claimed it was after this event that Ms Lewinsky was transferred from the White House to the Pentagon. It was not clear if the alleged witnesses were Secret Service agents who guard the President and White House staff. The Secret Service told another news network it was unaware of any such incident.
Although Ms Lewinsky is heard on audiotapes saying that no one observed her and the President, her attorney, Mr William Ginsburg, said yesterday that if the report turned out to be true, it could make it more difficult for her to obtain the complete immunity from prosecution that she now seeks from Mr Starr. She wants total immunity from prosecution before agreeing to tell everything she knows concerning her alleged affair.
Negotiations continued all weekend between the lawyers about an immunity offer which if granted would make Mr Clinton's position extremely precarious, as he has sworn an affidavit denying any sexual relationship with Ms Lewinsky.
Mr Clinton is reported to have told friends that he had an emotional relationship with Ms Lewinsky but that no sex was involved.
As the rumours continued to swirl around Washington, Mr Clinton tried to give the appearance of business as usual. He continued to prepare for his State of the Union address next Tuesday and watched the Superbowl football final on television with friends at the White House.
Earlier he attended a Methodist church service accompanied by Mrs Hillary Rodham Clinton. He paused as reporters shouted questions at him but then passed into the church without answering.
On Saturday Mr Clinton met his foreign and security advisers to discuss a possible military strike against Iraq for its continuing refusal to co-operate fully with the UN arms inspectors. US patience is now said to be almost exhausted, but the Secretary of State, Ms Madeleine Albright, will make further diplomatic tours of allies' capitals before Mr Clinton orders a retaliatory strike.
Opinion polls at the weekend showed that the crisis is affecting the President's popularity. A Newsweek poll showed his approval rating had fallen seven points to 54 per cent over the past week. Fifty-two per cent of those surveyed said he lacks the honesty and integrity they expect from a president.
As a private White House poll is said to have shown a 15 per cent drop in his approval rating, Mrs Clinton "in battle mode" was rallying aides and friends to go out and defend the President. The former commerce secretary, Mr Mickey Kantor, has been drafted in from his private law practice to advise the President, and a former deputy chief-of-staff, Mr Harold Ickes, is also being utilised.
Mr Clinton's most pugnacious defender, the former political adviser, Mr James Carville, said on NBC television that "there's going to be a war. The friends of the President are disgusted by these kinds of tactics. We're going to fight and fight very hard."
But a former chief-of-staff, Mr Leon Panetta, urged that Mr Clinton go to the people directly to confront the damaging allegations of adultery and perjury. If they turned out to be baseless, it would be all right, but if the allegations were true, it would be better for Democrats if the Vice-President, Mr Al Gore, "became President and you had a new message and a new individual up there".
A leading Republican Congressman said it was too soon to talk about impeaching President Clinton for alleged perjury or obstruction of justice arising from claims by Ms Lewinsky that he told her to deny their affair in an affidavit. Mr Henry Hyde, chairman of the House Judicial Committee, said in TV interviews that there needed to be stronger evidence to back up these allegations before an impeachment move.
Time, Newsweek and US News & World Report will today carry detailed accounts of the taped conversations between Ms Lewinsky and her co-worker at the Pentagon, Ms Linda Tripp.
President's allies prepare to fight back; Tapes seem to support Lewinsky's claims; Clinton's reaction to Iraq could be coloured by personal considerations: page 15