The world body became powerless on Monday as an outage partially hit the United Nations headquarters in the afternoon, ahead of the ministerial debate at the General Assembly where India's External Affairs Minister Natwar Singh was to speak.

The proceedings at the General Assembly and in other UN offices, however, went on, although part of the building was enveloped by darkness after a fuse blew on the 28th floor. Business was usual in the building except that all the non-essential Secretariat staff were sent back home following the incident, described by the New York Police Department as minor.

There was no word when the power would be restored, nor when the UN website would be up and running, on which journalists from all over the world depend for the latest take on UN proceedings.

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Agency reports said, quoting UN Associate Spokesman Farhan Haq, that the accident also forced Secretary-General Kofi Annan to change the venue of his annual lunch with foreign ministers and ambassadors from five Security Council permanent members.

Reports in Washington Post said that Annan's chief of staff, Mark Malloch Brown, quipped during the lunch that the outage would give US Ambassador John Bolton the chance to prove his claim, made 11 years ago, that it wouldn't make a 'bit of difference' if the Secretariat lost its top 10 floors.

The remark drew a hearty laugh from the diplomats, their ministers and Annan himself, the diplomat said, according to the report.