The actor met the woman who almost brought down President Clinton at party after the Oscars ceremony on Sunday, where he lost out to Roberto Benigni in the best actor category.

The two got chatting, found their schedules coincided during the following week - and decided to meet up for the premiere.

"I was at home and didn't have a date," Sir Ian, 59, said. "She was coming to London and I thought, we want to give her a good welcome.

"We have just been up in Leeds. I have just been up working in the theatre and Monica has been signing books."

Sir Ian plays British film director James Whale in the movie

"Too many," added Ms Lewinsky, 25, who said of her partner for the night: "I think he is very charming. This is my first premiere. I'm very honoured to be here. I've had a warm reception, I appreciate that, thank you."

Sir Ian was philosophical about missing out on an Oscar for the film, in which he plays British film director James Whale.

"You have to imagine that you're going to win - and when you don't, you're depressed, but only for about half-an-hour.

"Then I went to four parties."

The film won an Oscar for writer Bill Condon, who won the best adapted screenplay prize. He was pleased to see the reception it received in London.

He said: "This is great over here. It's treated like a real movie."

Another star of the film, Brendan Fraser, added as he arrived at the Odeon West End in Leicester Square: "My heart is pumping and I'll tell you why - last time I was in this theatre was in 1977 to see Star Wars."