Theresa May has sought to re-focus the Conservative General Election campaign on the forthcoming Brexit negotiations after seeing Labour close the gap in the opinion polls.

Returning to campaign trail after the Manchester bombing and her attendance at the Nato and G7 summits, the Prime Minister said the choice on June 8 came down to who voters wanted to represent Britain around the negotiating table in Brussels - her or Jeremy Corbyn.

"The questions for this campaign haven't changed since I called it six weeks ago. Who do you trust to stand up for Britain, to negotiate for Brexit and get the best possible deal for Britain in Europe?" she told a campaign event in South West London.

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"Brexit matters because it is the basis of so much else - our economic security, our prosperity, our place in the world, the future of our public services, the prospects and opportunities for our children."

Her appearance came after a series of recent opinion polls showed Labour narrowing the gap, with some putting the Conservative lead down to single figures.

There has been anger within the party at plans in the manifesto to reform social care, only for Mrs May to have to backtrack on a proposal to scrap a planned cap on care costs.

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Addressing activists, Mrs May warned that the party only had to lose six seats in the election for its Commons majority to disappear, opening the way to Downing Street for Labour.

"That could mean in just 10 days' time, a government in chaos, Jeremy Corbyn in number 10, John McDonnell in the Treasury, Diane Abbott in the Home Office and Nicola Surgeon and the Lib Dems pulling the strings," she said.

"The Europeans know that if they have a weak government in a hung parliament that government won't be able to stand up for Britain.

"That is what this election is about. It is about leadership, it is about stability, it is about doing the right thing for Britain. It is only the Conservative Party that can provide that."

Mrs May refused to be drawn on what majority she would be happy with.

"I don't predict election results," she said.

"I called this election because what was clear to me was that other parties wanted to frustrate the Brexit negotiations."

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Told she seemed to be a bit of a glum bucket who had run a subdued campaign, she replied: "I think it's absolutely right that we suspended campaigning for a time after the Manchester attack and I think people have been careful to be respectful as they have started back into campaigning.

"I'm optimistic about what we can achieve for this country for the future but this is a crucial election and there is a very clear choice for people when they come to that poll on June 8."

Mrs May said that while thoughts would continue to be with the people of Manchester after last week's attack, it was important that people carried on with their lives and they did not allow the terrorists to disrupt their way of life.

She denied that a re-elected Tory government would be just as weak on security as she was claiming Labour would, saying that in office the Conservatives had changed the law to strengthen the powers of the security services.

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"In contrast, Jeremy Corbyn has said, I think he may even have used the word proud, but he has voted against and opposed every single piece of anti-terror legislation in his time in Parliament," she said.

"I'm willing to stand up for our national security and do what is necessary in the British interest. He's not."