A British government official has admitted that British and French nuclear-armed submarines collided deep under the Atlantic Ocean.

The anonymous official said the accident caused minor damage to both vessels, but released no radioactivity.

France's Le Triomphant, a nuclear missile submarine, is seen in this undated photo released by the French Navy February 16, 2009.

HMS Vanguard, Britain's first Trident class nuclear-armed submarine, and the French Le Triomphant, collided earlier this month.

The official said the Vanguard's collision did not affect its deterrent capability and nuclear safety was not compromised.