Former US defence secretary Robert Gates, who served under presidents George Bush and Barack Obama, focused on cuts to the UK Navy as particularly damaging. He said that for the first time since World War One, Britain did not have an operational aircraft carrier.
The Ministry of Defence has defended levels of spending within the military spending, and said that the UK had the best equipped and well trained armed forces outside of the US.
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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.