President Clinton is reportedly being advised to admit to some sexual intimacy with Ms Monica Lewinsky when he testifies before a grand jury on Monday, to avoid being caught in a "perjury trap".
The White House press secretary, Mr Mike McCurry, has reacted sceptically to these reports and warned journalists that they are speculative. But it is significant that the reports have not been denied.
President Clinton's mood was described as "buoyant" as he celebrated his 52nd birthday, due in five days, at a surprise party with members of the White House political staff.
He also spent 40 minutes talking on the telephone with President Yeltsin about the Russian economic crisis.
As anticipation mounts in Washington over the President's testimony, the latest public opinion polls show that Americans are confused about what they think the President should do when he testifies. A CNN/Gallup poll shows 26 per cent would lose confidence in the President if he admitted having an affair with Ms Lewinsky, and 33 per cent would lose confidence if he denied it.
In what is widely seen as a "trial balloon" by the White House, the New York Times and other media have reported that the President has had "extensive discussions" with his inner circle about whether to admit he had "intimate sexual encounters" with Ms Lewinsky.
This would allow him to acknowledge a specific type of sexual behaviour while still maintaining that he told the truth when he testified under oath in January that he never had "sexual relations" with Ms Lewinsky, the newspaper article says.
She has now retracted her denial of last January and admitted to the grand jury that she did have some form of sex with the President. She has been given immunity from perjury charges, but Mr Clinton could risk being accused of perjury if he repeats his denial to the grand jury on Monday.
The independent counsel, Mr Kenneth Starr, is also believed to have received the results of DNA tests on a dress which Ms Lewinsky claims has evidence of a sexual encounter with Mr Clinton. But the President's lawyers have apparently been kept in the dark about the results.
Polls show that three-fourths of Americans believe he had sex with the former White House intern, so for him to admit it now would not damage him politically, it is argued. Because of the way "sexual relations" was defined when he testified last January, Mr Clinton could still maintain that he did not commit perjury.
He said publicly three weeks ago that he would testify this time "completely and truthfully". But another tactic being discussed is that he make some admission to sexual intimacy and then refuse to answer any further questions, pleading his right to privacy.
Some of the President's advisers are also urging him to make a statement to the American public after his confidential testimony, which will probably be leaked in some form late on Monday or soon afterwards. In this way Mr Clinton would be able to explain his relationship with Ms Lewinsky in his own terms.
Meanwhile, Mr Starr will be completing his expected report to Congress on whether he has found evidence of a crime for which the President could be impeached. The latest poll shows that 76 per cent of Americans oppose impeachment and 26 per cent are in favour, but these views could change following the President's testimony on Monday.