Scientists urge cutbacks in U.S. nuclear arsenal

The group, mostly physicists at major U.S. universities who have collectively won 23 Nobel Prizes, said that the existing U.S. weapons program was undermining the nation's security.

Organized by the Union of Concerned Scientists, the group called for the U.S. to reduce its weapons inventory to 1,000 bombs, from about 4,500 to 6,000 currently, and to cease its capability to launch missiles in minutes.

Richard Garwin, designer of the first hydrogen bomb, is among the scientists -- dominated by California academics -- who signed the statement.