To his face and on the love notes she sent him - including one attached to a sexually provocative tape she had delivered to his office one evening by courier - Monica Lewinsky's nickname for the President was Schmucko.

To her friend Linda Tripp, in whom she confided about the affair for hours at a time, she referred to him as the Big He. Later, when she realised the trouble she was in, she called him the Big Creep.

At first, it must have seemed like a dream, or at the very least like the script from Rob Reiner's film, The American President, in which Annette Bening, playing an environmentalist activist, finds herself dating the president, played by Michael Douglas.

There was only one difference. In the film, the president was widowed. Hillary Clinton is very much alive, and Ms Lewinsky knew the relationship was doomed. According to her friend, the bubbly young intern, who had arrived armed with hope, ambition and a degree in psychology from Lewis and Clark College in Oregon, was in love.

How could she have known in November 1995, when she slipped on her revealing black dress and headed for a White House party, that that night would be the start of an affair that might lead to the end of a presidency? Her charm and hard work as an intern for the then chief-of-staff, Leon Panetta, had paid off, and she had been given a junior secretarial job. The future must have seemed stellar. She caught the President's eye as he was dancing. There was no looking back.

Sometimes she would phone him six times in an hour and he would not reply; then, the next evening, he would call her at 2 a.m. He would buy her dresses and ply her with photographs of him in black tie, standing in the Oval Office behind his desk.

She would leave him letters and poems and, as the affair unfolded over the months, fabricate any excuse to visit his office; a fact which did not go unnoticed by the then deputy chief of White House staff, Evelyn Lieberman. After a run-in, White House personnel arranged for her to be transferred to another $32,000 position at the Pentagon.

Ms Tripp, a veteran civil servant, had already been working there for two years, and the two women became firm, if ostensibly odd, friends. Ms Tripp, a divorcee and single parent, aged 49, appeared to take a vicarious thrill from listening to Ms Lewinsky (then 22) recounting her astonishing tales with a mixture of passion and distress.

"She was a good, empathetic listener," said a colleague. Others noted that Ms Lewinsky would often discuss her personal life out loud, once announcing to no one in particular that she had had a brief liaison with a high-ranking Pentagon official.

But her affair with the President allegedly continued; their assignations taking place in the late afternoon or occasionally at weekends, when she would slip into the White House. Once, in the middle of the day, the two lovers disappeared into the small study off the Oval Office.

But how could she manage to keep the affair a secret, Ms Tripp, who started taping their conversations last August, once asked? "I have lied my entire life," Ms Lewinsky shrugged.

The affair was not to last. Mr Clinton seemed bored, and Paula Jones's lawyers were determined to use other women's experiences to suggest a pattern of sexual harassment. Terrified she would be questioned under oath, Ms Lewinsky was desperate for him to end the Jones case.

BY mid-December Ms Tripp told Ms Lewinsky that she would have to testify herself, and that she was not prepared to lie. She would tell Ms Jones's lawyers that she knew Ms Lewinsky had been having a long-standing affair with Mr Clinton.

Still unaware that her supposed friend had been taping their conversations, Ms Lewinsky begged her not to, and said she had been taking advice from the President's friend, Vernon Jordan, who had told her to lie on her affidavit. Mr Clinton had also told her to deny the affair. After Christmas, seeking a move to New York, Ms Lewinsky was offered a job with Revlon, referred by a director of the firm which owns the cosmetics company. She was also interviewed by the ambassador to the United Nations, Bill Richardson, who on Thursday issued an odd denial that the President had set the job up. In the event, she turned it down.

Last Saturday, as the President sat facing Ms Jones's lawyers, denying he had harassed her or had had an affair with Ms Lewinsky, his ex-mistress was pacing her apartment alone. Less than 24 hours earlier, she had been informed that Ms Tripp had been taping their conversations and that Kenneth Starr, the special independent investigator, was now investigating her.

There are no tapes to record her reply.