RUSSIA knew about the failed Trident missile test at the centre of an alleged No 10 cover-up, a former head of the navy has suggested.

Lord West, who was also the UK’s security minister until 2010, said he was sure the Russians were “aware” of the misfire of the nuclear weapon when it happened last summer.

He also ridiculed the UK Govern- ment’s continued attempts at secrecy.

Defence Secretary Sir Michael Fallon has refused even to reveal the date of the test. But Lord West said if he wanted that information he could telephone Russian leader Vladimir Putin “and he would probably tell me”.

He was speaking as he gave evidence to the Commons Defence Committee during a special convened session following concerns over the incident, which was first revealed over the weekend by the Sunday Times.

Lord West told MPs the test was a type carried out by the UK only once every four years.

He added: “I think one should be as transparent as one is able to.

“When you know it is being monitored by people like the Russians, when you know all that is done, it is a silly thing to do to try and hide it.”

He added that in the past the Russians had used a ship to monitor Trident “and of course they monitor it from space as well”.

He added: “I’m sure they are very well aware that it didn’t go all the way down ... or wherever it is supposed to go.”

He went on: “If anyone thought this wasn’t going to come out, they are living in cloud cuckoo land.

“This is a big bonanza occasion, we do this once every four years, it was inevitably going to come out.”

He also admitted the Royal Navy had once accidentally fired a surface-to-air missile at Wales.

But he told MPs defence bosses did not think that blunder was important enough to inform the Prime Minister.

He said: “Years ago, we had an aircraft missile called the Seaslug missile and we fired one into Wales.

“Those sort of things happen, but you don’t go and talk to the Prime Minister about that ... unless their constituency happens to be there.”

At the hearing. the chairman of the committee, Conservative MP Dr Julian Lewis, criticised what he said was the “unnecessary” secrecy of the Government.

On Monday Theresa May was forced to admit she had known about the misfire before MPs voted to replace the nuclear deterrent.

She conceded she had been briefed on the misfire a day having given a television interview the previous day in which she refused to say four times whether or not she had been informed.

The Trident incident happened in June, when David Cameron was still prime minister.

But Mrs May was told about it when she assumed office in the wake of the Brexit vote and Mr Cameron’s resignation.

Senior Tories have accused their own government of a cover-up.

On Monday, CNN reported that an unnamed US defence official had confirmed an unarmed Trident II D5 missile had veered off course after it was launched from a Royal Navy submarine off the coast of Florida.

US officials reportedly asked the UK Government not to publicise the results of the test.

The SNP has accused ministers of insulting the intelligence of voters by claiming Trident’s capability is “unquestionable”.

Meanwhile, former Royal Navy whistleblower William McNeilly said he felt vindicated after he warned of safety failings with the nuclear system. He told the RT (Russia Today) TV channel: “I warned about this exact event over a year before it happened.”