A former British Navy chief has compared the government's alleged cover-up over a failed Trident missile test to the secretive actions of North Korea.
Admiral Lord West claimed it was "bizarre" for the authorities to keep the malfunction under wraps.
"From what the Government say there was a minor glitch with the missile and they are quite happy with the system still, in which case go ahead and let people know," West told BBC Radio 4's Today programme on Monday (23 January)
"Otherwise we are a bit rather like the Soviet Union used to be, or like North Korea or China, where they won't admit to things going wrong."
West, who served as defence minister in Gordon Brown's Labour government, made the comments after The Sunday Times claimed an unarmed Trident II D5 missile went off course during a test firing in Florida in June.
The incident, under David Cameron's watch as prime minister, happened just weeks before a House of Commons vote on the renewal of the nuclear weapons system.
Theresa May, then Home Secretary, refused to say whether she knew about the malfunction ahead of the vote.
"I have absolute faith in our Trident missiles," she told BBC One's Andrew Marr show.
"When I made that speech in the House of Commons, what we were talking about was whether or not we should renew our Trident."
The Defence Secretary Michael Fallon is expected to face an urgent question in the House of Commons on Monday afternoon. But Angus Robertson, the SNP's Westminster leader, has called on May to personally explain to Parliament what had happened.
"It would be utterly unacceptable, and deeply serious, if it turns out that this information was deliberately kept from MPs at the time of the renewal vote for the Trident weapons of mass destruction programme," he said.
"Parliament and the public have a right to know if these reports are true, and there must be full disclosure about what happened, who knew, when they knew, and why the House of Commons wasn't informed. The prime minister cannot continue to dodge the question."
Trident operates a continuous at-sea nuclear deterrent. That means one of the programme's four nuclear submarines, which are based in the Faslane area of Scotland and operated by the Royal Navy, is always on patrol.
These Vanguard-class submarines are around 491ft in length, or over twice the size of two Boeing 747s, and powered by steam. A nuclear reactor inside the underwater vessels boils sea water, the steam from which is then used to propel them.
The four submarines – HMS Vanguard, HMS Vengeance, HMS Victorious and HMS Vigilant – are capable of carrying 16 Trident II D5 ballistic missiles, produced by the American arms manufacturer Lockheed Martin, each armed with up to eight nuclear warheads. As it stands, each submarine only carries three Trident missiles.
Their power and precision is stunning. Each missile is 44ft long, 83 inches in diameter, capable of exceeding speeds of over 13,000mph, and can hit targets up to 7,000 miles away, accurate to within a few feet.
The payload – or, just how powerful the destructive force of each warhead is – isn't known publicly. But, according to a parliamentary research paper, it is thought to be around 100 kilotons.
To put that in context, the atomic bomb Little Boy, dropped on the Japanese city of Hiroshima during the Second World War, had an energy yield of around 15 kilotons, killing as many as 80,000 people instantly. Therefore, a single warhead in a Trident II D5 missile has the destructive power equivalent to over six Hiroshimas at once.
The current fleet of submarines will come to the end of their working life in the 2030s. Because of the length of time it takes to build a new fleet, the issue of renewal is timely now and a decision must be made in 2016. The Trident missiles have already had their lives extended until the 2040s, when they will expire and be decommissioned.
But the cost of doing this – renewing and upgrading the nuclear deterrent infrastructure – is enormous. Estimates put the total cost, when the new submarine fleet comes into action in the 2030s, at £100bn ($147bn, €138bn). In 2013/14 alone, the NHS England budget was £95.6bn.