The decision not to hold the annual meetings in Washington on Sept. 29-30 came almost a week after devastating air strikes on New York's World Trade Center and the Pentagon, just outside Washington. The meetings are used by the guardians of the global economy to chart policy for the months ahead.
The meetings were expected to focus on how to avoid a global recession, as economic growth in the United States, Europe and Japan has stumbled badly - a situation only made worse by the events of the past week.
"In consultation with the U.S. authorities and other member governments, the World Bank Group and the IMF have decided not to hold their annual meetings on Sept. 29-30," World Bank President James Wolfensohn and IMF Managing Director Horst Koehler said in a statement.
"The normal business of the bank and the fund will not be interrupted. Alternative arrangements for conducting the required business of the meetings will be determined."
There was no word on the fate of a parallel meeting of central bankers and finance ministers from the Group of Seven rich industrialized countries - the United States, Japan, Canada, Germany, Britain, France and Italy - who had been due to meet in Washington on the same weekend.
The G-7 normally meets immediately before the spring and fall gatherings of the IMF and World Bank.
Should it be necessary to move that meeting, Italy has offered to substitute as host.
After last week's attacks, it became highly unlikely that the IMF/World Bank meetings could proceed in Washington.
In a joint statement, officials of the two multinational lending agencies headquartered in Washington said their normal operations would not be affected by the cancellation.
"This decision was taken out of deepest respect and sympathy for the families of all those touched by the horrific events of last Tuesday, and in order to dedicate law enforcement personnel fully to the extraordinary and immediate priorities at hand," Wolfensohn said.
The two officials said that they expect to return to their regular schedule of meetings next year, which would mean a spring meeting of finance ministers from the 24 nations on the steering committees for both the IMF and World Bank.
Koehler and Wolfensohn said they would find other ways to deal with the issues that would have been addressed at the annual meetings.
The operation to recover bodies from the Pentagon and clean up the military nerve center has left emergency workers and police in the nation's capital stretched to their limits.
"We would also like to express our heartfelt appreciation to the District of Columbia, in particular, for its hard work to prepare a secure environment for the meetings," he added.
The meetings had already been scaled back ttwo days because of the threat of violent protests by groups which do not agree with the institutions' policies.
As many as 100,000 protesters had initially been expected.
Protests at international gatherings have grown increasingly violent recently, with one protester killed in clashes with police at a mid-July summit in Genoa.
On Sunday, the Mobilization for Global Justice, the umbrella group for many of the protest organizations, said it was calling off its street demonstrations but would continue with plans for a "people's summit" of teach-ins and discussions Sept. 26-28.
"Our decision to postpone was made out of respect for the victims of this tragedy," the group said in a statement.
Last Friday, the AFL-CIO, Friends of the Earth and Oxfam America all announced that they were pulling out of the planned demonstrations.
And another organizing group, the International Action Center, said it would instead hold a "march against war and racism" in Washington on Sept. 29.
Still, with so many foreign dignitaries to protect, security was a major concern.
Washington had originally hoped to use as many as 1,000 New York police to help keep the summit secure, but those officers are now needed in their home city following the disaster there.
Last week Washington Mayor Anthony Williams and Police Chief Charles Ramsey both called for the meetings to be called off, adding to expectations that a cancellation announcement was imminent.
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