In a move which could put his party at odds with its Conservative coalition partners, the Chief Secretary to the Treasury admitted Britain faces a "big decision in 2016" over alternatives to the current weapon system.
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The Duke and Duchess of Cambridge met young people who have battled mental health issues on Saturday.
Former Chancellor Lord Geoffrey Howe was Margaret Thatcher's longest-serving Cabinet minister, also taking on the role of Foreign Secretary.
Lord Geoffrey Howe is known by many for his resignation speech which was seen as the catalyst which destroyed Margaret Thatcher.