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 100 leaders did not agree on concrete proposals, but the meeting has raised hopes for concrete international agreement next December.
The speech was OK, passionate at times and certainly well received, but did not display the passion of past speeches.
The brother-in-law of a British hostage being held by Islamic State militants in Syria, says he is scared by US airstrikes in the country.