THE MoD has defended its “unjustifiable” plans for a Trident replacement after analysts claimed it could “sink” the defence budget.

Anti-nuclear campaigner Bill Kidd MSP – co-president of the international Parliamentarians for Nuclear Non-Proliferation and Disarmament (PNND) group, which covers more than 75 nations – hit out at Westminster’s “obsession” with the £31 billion project after serious concerns among defence experts emerged.

They follow a recently published review of UK defence capabilities and targets that referred to the Dreadnought project as the “ultimate guarantee” of domestic security.

The scheme – opposed by the SNP, Greens and Scottish Labour – includes renewing the nuclear deterrent and building four new submarines.

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But, according to naval specialist Trevor Taylor, of the Royal United Services Institute think tank (RUSI), the programme is a serious threat to the defence budget, which the National Audit Office has warned may face a £15bn funding gap over the next 10 years.

The MoD has already drawn down from the Treasury-held £10bn contingency pot for the project, securing £600 million in March.

Speaking to the Financial Times (FT), Taylor said: “Can Dreadnought sink the defence budget? The answer is yes.”

On the complexity of the scheme, he said: “Nuclear subs are the most demanding defence project. You do not get to build a prototype, you have to get it right first time.”

The new vessels will be built by BAE Systems at its Barrow-in-Furness yard, with input from Rolls-Royce and Babcock International.

The project will be overseen by the Submarine Delivery Agency, which was set up to handle the enormous project.

Richard Scott, naval consultant editor at defence magazine Jane’s, told the FT there is uncertainty among both MoD and Royal Navy officials on the impact of Dreadnought on the overall defence budget, saying: “You hear comments about the disproportionate impact the deterrent has on the overall defence budget.

“Some people are asking ‘can we really justify this?’”

The National:

Kidd (pictured above), whose Glasgow Anniesland constituency lies around 30 miles from Faslane, home to the Trident fleet, blasted the controversial project, saying: “The cost of Trident renewal is enormous and unjustifiable, particularly when the Tories have slashed public spending elsewhere.

“It is increasingly obvious that the UK Government’s single-minded obsession with nuclear weapons is going to come at a huge cost to our conventional defence.

“The staggering revelation that even senior military officials are now questioning whether we can justify Trident renewal should give the Tories a reality check.

Independence will mean a Scotland free of nuclear weapons, rather than paying through the nose for these wasteful and immoral weapons.”

More than 600 people from around the world protested against the UK’s nuclear arsenal at the gates of HM Naval Base Clyde in September.

The Nae Nukes Anywhere rally also urged governments around the globe to abandon the weapons of mass destruction.

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The MoD told The National that Dreadnought “remains within its estimated cost”, and supports “thousands” of UK jobs.

A spokesperson said: “The Dreadnought programme will deliver the most advanced submarines ever made for the Royal Navy, built to counter the threats of 2060.

“While these submarines will set the foundation of defence for generations to come, we continue to invest in cutting-edge capabilities in air, space, cyber, land and sea.

“Nuclear ballistic submarines are among the most complex building projects undertaken and considered the engineering equivalent of building a space shuttle.

They added: “Regular and rigorous reviews ensure the programme remains within budget and on schedule to deliver the first boat in the early 2030s.”