A former Royal navy submarine engineer turned Trident whistle-blower has alleged a fake ID is all it takes to access Britain's nuclear submarines.

William McNeilly raised several security concerns about Britain's nuclear weapons systems in Scotland in an interview with RT (formerly Russia Today).

"All you need to get on board is a couple of fake IDs," he said. "Terrorist groups like Isis have already shown they can produce legitimate documents.

"Thousands of Royal Navy IDs go missing every year as well, so they could come across one."

He described going on patrol with 180 people who all brought unchecked bags on board.

"All it would take would be for one of them to have a bomb," he said.

The Defence Secretary Michael Fallon in Faslane last month, visiting nuclear submarine HMS Vigilant (Getty)

A Ministry of Defence spokesperson told The Independent: “Rigorous security measures are in place at HM Naval Base Clyde and it is nonsense to suggest otherwise.

"We simply do not accept that a fake ID would gain you access to a nuclear submarine.”

Mr McNeilly has previously claimed there is a "complete lack of concern for security" making Trident vulnerable to terror attack.

HMS Vigilant, one of Britain’s four Trident nuclear missile-armed submarines, at its Faslane base in Scotland (Getty)

He posted a 15-page document online claiming he witnessed a host of inadequate security checks while training with the Trident programme.

“You don’t even need your Dolphins, you don’t even need to be part of the Navy, any logical thinking person, and anyone with half a functioning brain cell can understand the risks," he told RT.

He also alleged the Government tells lies to protect its image of Britain as a nuclear state.

“It’s not the people that come first, not the land, not safety that comes first, they have shown in their own documents, not just my report, you don’t have to listen to me, you can go and do your own research and prove it yourself, they have shown that they will put nuclear weapons above the people and above the land.

"They have shown that they are willing to lie just to protect the image of nuclear weapons. Just so they can keep them.”

Giant 'Stop Trident' Projection Illuminates Houses of Parliament

Discussing his views on Trident, he told RT: "People don’t want the boats and we don’t need them. We’ve not needed them in the wars we’ve been fighting.

"Maybe we needed them in the cold war. They have served their time, they should be given respect for what they’ve done for our country during the cold war, but not now. Times have changed.

"It’s a new world and they need to wake up, create real change, create a sustainable system.”

Royal Navy's 16,000 ton Trident-class nuclear submarine Vanguard (PA)

The SNP have previously called a vote to scrap the UK's Trident nuclear weapons system.

MPs defeated the SNP's motion opposing Trident's renewal by 330 votes to 64.

The overall cost of replacing Britain's Trident nuclear systems would be £167bn - double previous estimates - according to recent calculations based on official figures.

Brendan O'Hara, the SNP's Defence spokesperson, told The Independent: "These revelations, if true, are extremely concerning. William McNeilly has pointed to the MoD's long history of secrecy and complacency at the nuclear base for some time. It was extremely disappointing that the MoD dismissed his dossier on safety concerns last year.

"Safety and security must be paramount with nuclear submarines. Safety blunders and serious security lapses have plagued Trident submarines at Faslane.