``The ABM treaty has served for many years as a cornerstone for maintaining global peace and security and strategic stability,'' U.N. spokesman Manoel de Almeida e Silva said.

Annan, he said, was concerned that abandoning the treaty would ``provoke an arms race, especially in the missile area, and further undermine disarmament and nonproliferation regimes.''

The secretary-general called on all countries to explore ''new binding and irreversible initiatives to avert such unwelcome effects,'' Almeida e Silva said.''

``The ABM treaty has served for many years as a cornerstone for maintaining global peace and security and strategic stability,'' he said. Annan had ``noted with regret'' the U.S. decision.

Rejecting Russian and Chinese opposition, President Bush gave formal notice on Thursday that the United States was abandoning the treaty in order to press ahead with a missile defense system.

The decision marked the first time in recent history that the United States has withdrawn from a major international arms treaty. The ABM expressly forbids deployment of missile defenses.

Copyright © 2001 Reuters Limited

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