“Your vote is more important than ever because every vote for me in this election will if I am returned as Prime Minister strengthen my hand in the negotiations that are about to start.

“But if you don’t vote at this election and if you don’t vote for me at this election you risk sleepwalking into the very real danger that Jeremy Corbyn will find himself in the hot seat, in the negotiating chair on your behalf.”

Mrs May’s speech came after she and Mr Corbyn faced a TV grilling at the hands of Jeremy Paxman and a live television audience.

She was given a tough time over her plans to reform social care but performed best on Brexit as audience members applauded her commitment to walk away from talks without a deal rather than accept a bad one.