UNITED NATIONS - After months of criticism, Secretary-General Kofi Annan decided that U.N. refugee chief Ruud Lubbers had to go because of the growing controversy over allegations that the former Dutch prime minister had sexually harassed female staffers.

Lubbers didn't go easily. He resigned Sunday but proclaimed his innocence, saying he felt insulted and accusing Annan of giving in to "media pressure."

At a meeting with Annan on Friday, U.N. diplomats said the secretary-general offered the U.N. High Commissioner for Refugees two choices - resign or face suspension and charges of breaking U.N. rules.

Allegations first surfaced last year that he had made unwanted sexual advances toward a female employee, identified in media reports as an American. But it was only on Friday that the British newspaper The Independent published the first detailed description of her allegations and statements from four other women who didn't file official complaints but claimed Lubbers sexually harassed them.

After defiantly telling reporters that Annan had not asked for his resignation and he intended to complete his five-year term, Lubbers flew home to Geneva on Friday. But after he left U.N. headquarters, Annan's office contradicted the refugee chief, saying the prime topic of the meeting was his future.

Apparently knowing what was coming, Lubbers, 65, decided to resign on Sunday before being suspended.

In his letter of resignation, Lubbers maintained his innocence, indicating that Annan wanted him to step down.

Annan had been criticized for months for rejecting the report from U.N. investigators who concluded that Lubbers' overall behavior indicated "a pattern of sexual harassment."

U.N. diplomats saw Lubbers' departure as part of a major effort to revamp the top U.N. leadership, pushed by the secretary-general's new chief of staff, Mark Malloch Brown, whose primary job is to improve U.N. performance and overhaul its management.