MPs have overwhelmingly rejected an SNP motion not to renew Trident, the UK’s nuclear missile system based at HMNB Clyde, by 330 votes to 64.

The motion – That this House believes that Trident should not be renewed – started a debate, with most of the SNP MPs attending.

On Monday, it was revealed the cost of renewing the system had risen to £31bn.

Ministers have promised a vote on the main Trident renewal decision.

Helensburgh and Lomond’s MP Brendan O’Hara started the debate, maintaining his position that Trident is "morally and economically indefensible".

He addressed the House of Commons at the debate on Tuesday afternoon, in which Labour MPs were told to abstain, although some rebelled and took part in the debate.

Brendan O’Hara, MP for Argyll and Bute and the SNP’s defence spokesman, said there was an "established consensus" among the political parties in Scotland opposing Trident.

He also said: “In recent weeks the Scottish Parliament again reaffirmed its outright and overwhelming opposition to Trident renewal.”

Mr O’Hara: “Trident is not a military weapon. Trident is a political weapon...which can never, and will never be used.”

Several SNP MPs spoke during the debate, raising questions of the cost of renewal, as well as the need for Trident if it will not be used – following claims from Labour Party leader Jeremy Corbyn who said he would not fire the weapons if he was Prime Minister. 

Toby Perkins, shadow defence minister for Labour, told the House his party was"committed" to a minimum nuclear deterrent.

He also said it was "ludicrous" to suggest there was not differing opinions on Trident within the Labour party, and the recent vote at Scottish Labour’s party conference would be "considered" when deciding party stance on the renewal of the nuclear deterrent.

It is expected Labour will conduct a defence policy review to gauge widespread opinion on renewal.

Following Mr O’Hara’s comments that Scottish politicians "overwhelmingly" reject opposition, Angela Smith, Labour MP for Penistone and Stockbridge, said it was a UK matter – not just a Scottish matter – adding: “It deserves a focus that is not a narrow-minded, nationalist outlook.”

Mr Perkins agreed, adding Trident was "really important" to the supply chains right across the United Kingdom.

Several Conservative MPs said there was an "essential" need for a continuous at-sea nuclear deterrent.

The debate took place on the House of Commons’ Opposition Day.

Speaking after the debate, Mr O’Hara said: “There is no moral, economic or military case for Trident, however today (Tuesday) saw moral bankruptcy from Labour. The vast majority of their MPs abstained, including their own Scottish MP Ian Murray.

"This is in direct contradiction to Scottish Labour party policy. Only six voted with the SNP with 14 voting with the Tories to support Trident.

“The SNP position remains clear – we are opposed to the renewal of this obscene, redundant and eye-wateringly expensive nuclear arsenal, and we will continue to make the case for it to be scrapped.”

The debate was held hours after a former Defence Secretary told the BBC the nuclear weapons could be rendered obsolete by cyber attacks.

Lord Browne, an ex-Labour minister, told the BBC unless "weak spots" were protected, there was "no guarantee" of a reliable nuclear deterrent.

Ex-Conservative Defence Secretary Sir Malcolm Rifkind played down the risk.

Lord Browne, who was defence secretary between 2006 and 2008,said that ministers had an ‘obligation’ to assure MPs all parts of the nuclear deterrent had been assessed against the risk of a cyber attack and that protections were in place.