On 18 July, the House of Commons will vote on whether to renew Britain's controversial, ageing Trident nuclear weapons system. The decision on the fate of Britain's four Vanguard nuclear submarines will take place shortly before Parliament's summer recess.

Getty Images photojournalist Jeff J Mitchell spent some time with the crew onboard HMS Vigilant, one of the Royal Navy's four Vanguard-class submarines carrying the Trident ballistic missile, the UK's nuclear deterrent.

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Royal Navy personnel work in the control room on HMS VigilantJeff J Mitchell/Getty Images
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Warrant Officer Johnston poses in the weapons room on HMS VigilantJeff J Mitchell/Getty Images
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Able Seaman Smith and Able Seaman Davies relax on their bunks on HMS VigilantJeff J Mitchell/Getty Images
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Lieutenant Ross works in the missile control centre on HMS VigilantJeff J Mitchell/Getty Images
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Lieutenant Benson and Warrant Officer Firth pose in the missile compartments on HMS VigilantJeff J Mitchell/Getty Images
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ET Hicks poses in the auxiliary machinery space on HMS VigilantJeff J Mitchell/Getty Images
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Warrant Officer Firth poses for a photograph in the missile compartments on HMS VigilantJeff J Mitchell/Getty Images
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Warrant Officer Gray makes his way through a hatch on HMS VigilantJeff J Mitchell/Getty Images
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Lieutenant Alexandra Olsson poses in the control room on HMS VigilantJeff J Mitchell/Getty Images
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STD Skinner poses in the ward room on HMS VigilanJeff J Mitchell/Getty Images
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LOGS Howard poses in the ship's officeJeff J Mitchell/Getty Images
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Surgeon Lieutenant Tweed poses in the sick bay on HMS VigilantJeff J Mitchell/Getty Images
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Chef Sewell prepares a curry in the galley on HMS VigilantJeff J Mitchell/Getty Images
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Junior rates relax in the mess on HMS VigilantJeff J Mitchell/Getty Images
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Junior rates play Playstation games in the mess on HMS VigilantJeff J Mitchell/Getty Images
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Royal Navy security personnel stand guard on HMS Vigilant at Her Majesty's Naval Base, ClydeJeff J Mitchell/Getty Images
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Royal Navy personnel go through training exercises in a bridge simulator at Her Majesty's Naval Base, ClydeJeff J Mitchell/Getty Images
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Royal Navy personnel respond to a fire in a control room of a Vanguard Class ship simulator at Her Majesty's Naval Base, ClydeJeff J Mitchell/Getty Images

The government says the nuclear deterrent is vital to keep Britain safe in an increasingly hostile world, but some opposition figures say it is indefensible to spend billions on renewing the programme at a time of austerity cuts. Labour had been a supporter of renewal but its leader Jeremy Corbyn, an anti-war campaigner, is opposed to the plans. The Scottish Nationalist Party wants the Trident submarines, which are based in Scotland, to be scrapped.