UN refugee agency chief Ruud Lubbers has offered to resign, following allegations of sexual harassment.

In a letter to Secretary General Kofi Annan, Mr Lubbers said he was quitting because of a lack of confidence in him.

The move comes two days after Mr Lubbers denied allegations contained in a leaked internal UN report.

It said that the former Dutch Prime Minister had engaged in unwanted physical contact with a female staff member at his agency.