Dominique Strauss-Kahn said he rarely attended sex parties because he was “saving the world” and had “other things to do”, as he gave evidence for the first time in his trial on charges of participating in orgies with prostitutes.

The former head of the International Monetary Fund, who with 12 others is accused of “aggravated pimping as part of a group”, insisted yesterday at his trial in the northeastern city of Lille that he was unaware the women he had sex with were prostitutes.

“When you read the criminal complaint, you get the impression it was this frenetic activity,” the 65-year-old Mr Strauss-Kahn, wearing a black suit and silver tie, told the court in a calm voice. “But it was four times a year, not more than that. It wasn’t this out-of-control activity.”