UNITED NATIONS — The U.N. refugee chief, Ruud Lubbers, told Secretary-General Kofi Annan yesterday that he was resigning because Kofi displayed a lack of confidence in him over sexualharassment allegations.

In a letter of resignation Lubbers wrote: "For more than four years I gave all my energy to UNHCR (U.N. High Commissioner for Refugees). Now in the middle of a series of problems and with ongoing media pressure you apparently view this differently."

The United Nations is also under fire for the scandal-tainted oil-for-food program in Iraq and sexual abuse by peacekeepers in the Congo.

After allegations first surfaced last year that Lubbers had groped a 51-year-old female employee, Annan said there were insufficient grounds to fire him.

But on Friday, Annan consulted lawyers, clearly angry after a British newspaper published details of a previously secret U.N. investigation of allegations that Lubbers sexually harassed a female employee. That report included graphic details.

Lubbers noted the initial complaint against him "could not be substantiated." In one of the other three cases mentioned by the newspaper, the staff member had "adamantly refused to file a complaint," he added.

The other two incidents were "either misconstrued or simply hearsay," he said.

Lubbers, 65, who was Dutch prime minister from 1982 to 1994, is independently wealthy and was working as UNHCR for $1 a year. He has donated his salary, estimated at about $300,000, and travel expenses to the United Nations each year.