Jo Swinson has admitted it would take a “strange thing” for her to won the general election and that she regrets some of the harsh benefit cuts imposed by the Coalition.

The Liberal Democrat leader was told she had made herself look “ridiculous” after the party’s campaign put her forward as a likely prime minister.

Asked, repeatedly, if she really believed she could enter No 10, Ms Swinson replied: “We do live in a world where sometime strange things have happened in politics.”

And, quizzed about “harsh and uncaring” benefit cuts, when she was a Coalition minister, she acknowledged: “We didn't get everything right.”

In recent weeks, the Lib Dem poll ratings have slumped – throwing into a harsh light the party’s campaign leaflets describing Ms Swinson as ‘Britain’s next prime minister’.

On the BBC’s Question Time programme, a voter drew laughter as he asked her if she now recognised “how ridiculous that sounded”.

Asked if she was “still saying that you could be prime minister”, Ms Swinson admitted “things have got much more challenging”, blaming the ‘alliance’ between Boris Johnson and Nigel Farage.

“There’s still three weeks left in this campaign and, all I would say to anybody who thinks you can predict the outcome of the election in the middle of the campaign, ask Theresa May how that worked out,” she said.

However, put on the spot, she added that she “gets that it is big ask” – and that it would be a “strange thing” if she emerged as prime minister on 13 December.

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On austerity – which the Lib Dems now wish to reverse, despite Ms Swinson serving as a minister in the Cameron-Clegg coalition – she admitted: “We also had plenty of fights with the Conservatives and we won some of those fights and we lost some of those fights and I am sorry that we did not win more of those fights in coalition.”

She was also challenged on the Lib Dem policy of revoking Article 50 to stop Brexit, but she insisted: “We are being very straightforward as a party that we want to stop Brexit.

“You might agree with us, you might disagree with us. I don't think you can accuse us of not being upfront about wanting to stop Brexit. We've been crystal clear about that from the very beginning.