David Cameron has opened his speech at the Conservative Spring Forum by saying that his party came to power in "perilous" times and that it was "wrestling with historic debts".
He added: "We are here to fight, we are here to win and we have never been more up to the task of turning our country around."
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It will be a cloudy and at times damp morning across much of the UK, apart from the far west where it will be dry and bright.
Barack Obama has returned to the political spotlight, campaigning for Democratic candidates ahead of upcoming elections.
The prime minister said there was a "clear and urgent imperative" to give new impetus to stalled negotiations.