TRIDENT is a “symbol” which has no “military significance”, a former adviser to Bill Clinton’s administration has claimed.

Speaking on a BBC Newsnight special, Nancy Soderberg dismissed the need to replace the nuclear system and called instead for the UK to invest in more conventional weapons.

Soderberg said: “The US has a very vibrant nuclear umbrella over Europe.

“The role Trident missiles really serve is symbolic but not a militarily-significant addition to that.”

Citing the notion the system is a deterrent against attacks from nuclear nations like Russia, she went on: “I don’t think Vladimir Putin, even if he keeps a downward tyrannical slide, is seriously going to contemplate using nuclear weapons on Europe.

“There’s no reason, there’s no threat.”

Addressing the issue of increasing conventional weapons, she added: “It’s not like having one weapon or another, it’s what do we need right now in the world?

“We need more help now in the current fights with Isis – the air force, the intelligence, the drones trying to fight the threat of terrorism.”

Soderberg added that the real nuclear threat is “increasingly” coming from terrorists “getting hold of the loose nukes, the loose material”, which gives a “very powerful signal to move forward” with reducing the number of nuclear weapons held by governments.

In November, the Government revealed the estimated bill for replacing the ageing Trident fleet has risen by £6 billion.

The total cost now stands at £31 billion, compared to a previous estimated of £25 billion.

The Ministry of Defence is also to hold a further £10 billion in case of further increases in costs.

However, the overall costs of replacing and maintaining the fleet could reach £167 billion, according to calculations published last October.

The Government has not yet set out the timetable for voting on the issue, but SNP defence spokesman Brendan O’Hara yesterday restated his party’s opposition to the Clyde-berthed system.

O’Hara, who also took part in the Newsnight special, said: “Nancy Soderberg’s comments hit the nail on the head.

“Trident is the UK’s ultimate virility symbol – it allows David Cameron to wield what remains of imaginary influence – proving beyond any doubt it is not a military asset, it is a political one.

“At £167 billion it is an obscenely expensive, immoral and completely redundant one.

“The SNP will vote at every opportunity to oppose Trident renewal and stop it being dumped on the Clyde once and for all.”

Meanwhile, the police force which guards UK nuclear weapons bases and other military facilities says it is so overstretched that security is at risk.

In a report by its overseeing committee, the Ministry of Defence Police said its 2,700 officers are carrying out “excessive overtime” to police 120 sites.

The concerns have been raised just one month after it was revealed that the number of unauthorised entries to UK military bases almost doubled in one year from 24 to 44.

According to the MoD, other breaches in security also rose by 50 per cent to 1,600 in 2015 and the incidents of theft or loss of classified material also went up.

The force launched a recruitment drive three years ago but figures increased by only five officers in 2014-15 as a result of retirements and other losses.

MoD police committee chair,an David Riddle said performance was currently “acceptable” but had only been achieved “with huge amounts of overtime working”, adding: “This is not sustainable without risks to employees and security.”

However, the MoD said the force plans to recruit 200 further officers within the next financial year and is currently “95 per cent manned”.

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