STAFF at a nuclear warhead facility that develops weapons for Trident will vote on strike action in a dispute over pay, a union has said.

The Prospect union said a ballot for its members at the Atomic Weapons Establishment - an arms-length body of the Ministry of Defence - would open on October 24 and run for a fortnight.

Its members have rejected a 5% pay award, while an additional lump sum payment offered was was still deemed inadequate, the union said.

"Safely maintaining the UK's nuclear deterrent is a complex and highly stressful operation that requires an extremely high level of dedication and training at all levels," Prospect General Secretary Mike Clancy said in a statement.

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"It should attract a commensurate level of pay and respect for these staff who keep the country safe."

Headquartered in Berkshire, the AWE develops and maintains nuclear warheads for Britain's Trident nuclear deterrent based at Faslane.

The ballot comes as inflation hit 10.1% in September due to soaring food prices.