Prime Minister David Cameron on Thursday (April 4th) said at a question and answer session in Scotland that recent developments surrounding the threats from North Korea showed the continued need for a nuclear deterrent in Britain.
Cameron answered questions from a group of people after writing an article printed on Thursday morning in The Daily Telegraph, and after visiting the Vanguard-class submarine HMS Victorious, just off the coast of West Scotland.
Responding to a query regarding the real scale of the threat of North Korea, Cameron said no nuclear country should be underestimated.
"It has extremely dangerous technologies in terms of nuclear and its weapons. It has a new and relatively unknown leader, and obviously the noises it's been making in recent weeks and months are worrying and threatening," he said.
"But I think it's a good moment to stand back and ask ourselves about the dangers there are in the world, and the need to maintain strong defences. The fact is, as I wrote in a newspaper this morning, North Korea does now have missile technology that is able to reach us," he added.
The UK's nuclear defence system, called Trident, needs to be renewed shortly after the next 2015 general election, but the fact that Britain's four Vanguard class nuclear submarines reach the end of their service lives in the 2020s means it cannot be put off for long.
Britain's big debts will weigh on any decision to commit billions of pounds to a successor system to Trident.
Cameron said however that the ultimate deterrent was worth the price.
"What will a country like North Korea be like in 10 years, 15 years, 20 years? How certain can we be? How certain can we be that its weapons will be secure? How certain can we be that they won't share weapons and technology with other countries?" he said.
"We can't be sure of those things. And that is why I think it's so important to maintain strong defences, to maintain our nuclear deterrent, to maintain that insurance policy against the risks that there are in our world, and North Korea is a good example of that," he added.
Cameron's comments put him at odds with his Liberal Democrat coalition partners who want to find a cheaper alternative to Britain's multi-billion pound submarine-based Trident nuclear missile system to try to save money at a time when the nation's finances are mired in debt.
Cameron has played down the costs, saying Britain's nuclear capability cost less than 1.5 percent of what the government spent on welfare benefits each year.
Cameron, the leader of the Conservative Party, the senior member of the two-party coalition, said he had not seen any evidence there were cheaper ways of providing a credible alternative to the "ultimate weapon of defence", saying the nuclear threat had grown since the end of the Cold War.
The opposition Labour party, which is ten points ahead of Cameron's Conservatives in the polls, is reviewing its own policy on Trident. For now, one of the four submarines is always on patrol.
One money-saving idea is to pare that schedule back.
Cameron also used the trip to Scotland to explain why he thought Scots should vote to stay part of Britain in an independence referendum next year, but the pro-independence Scottish National Party (SNP) accused him of scaremongering after he said Scottish defence jobs were more secure while Scotland was part of Britain.
The SNP has said it does not want nuclear weapons in an independent Scotland.