The UK government has been accused of a cover up after failing to disclose that an unarmed nuclear missile may have been mistakenly fired at the US mainland.
The serious malfunction happened last June just ahead of a UK parliament vote on renewing Britain's nuclear deterrent, the Sunday Times has reported.
The paper quoted an unnamed senior naval source as saying the missile may have veered off in the wrong direction towards the American mainland when it was fired off the coast of Florida from a nuclear Trident submarine.
Theresa May has refused to say whether she knew that a Trident missile had misfired just weeks before a Commons vote on the future of the nuclear deterrent.
The Prime Minister declined four times to answer questions about whether she was aware that the launch of an unarmed Trident II D5 missile from a British submarine off the coast of Florida in June malfunctioned.