Liberal Democrat leader Tim Farron has refused to rule out taking his party back into a coalition government with the Conservatives.
"Any serious politician who rules out going into power isn't a serious politician," he told IBTimes UK on Monday (5 December).
"This is the problem I've got with Jeremy Corbyn, who is somebody who is a perfectly nice man but seems to actively not want to be in power. I want to make a difference."
Farron added: "It's not up to me to choose who the Liberal Democrats go into power with if the Liberal Democrats don't get a majority.
"That's up to the electorate [and] that's how the arithmetic worked out in 2010."
The comments come just days after Liberal Democrat Sarah Olney beat independent candidate and former Conservative MP in the Richmond Park and North Kingston by-election on 1 December.
The Greens decided not to contest the West London seat in a bid to boost Olney's chances, while transport expert Christian Wolmar unsuccessfully stood for Labour.
Wolmar attracted less than 5% of the vote share (3.6%) and therefore lost his £500 deposit. Farron said the defeat is "something that perhaps they shouldn't weep too much about".
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But the Liberal Democrat leader claimed Labour face losing support across the UK because the party has waved a "white flag over Brexit".
Shadow Chancellor John McDonnell has backed the UK's split from the EU as an "enormous opportunity" and warned blocking the process would put Labour on the side of "corporate elites".
Corbyn, meanwhile, has promised his party will table an amendment to any Article 50 bill tabled before the House of Commons.
The draft legislation may be needed to trigger the official mechanism to split from the EU if the government loses its historic appeal at the Supreme Court.
The Liberal Democrats, who now have nine MPs in the Commons, are pushing for a second referendum on the terms of the UK's exit from the economic and political bloc.
"Our view is that the one thing that would stop us voting for Article 50 is if the government [don't] allow the will of the people to be expressed at the end of the process," Farron said. "Sadly the Labour Party haven't joined us in that, they seem to be waving the white flag over Brexit and that is a shame."
He added: "People are giving up [Labour] because they are not providing that moderate, progressive alternative voice to the Tories."
Theresa May has ruled out a second EU referendum and promised to trigger Article 50 by March 2017.
But the prime minister's plans could be delayed by the outcome of the Supreme Court case, with a final ruling expected in January 2017.
"The problem in this case is that we started this process with democracy and the government is now ending it with a stitch-up...It's definitely no way to end it if you want a peaceful consent and closure for the whole of the British people, however they vote in the June referendum," Farron said.
May, who succeed David Cameron in July, has also ruled out a snap general election, with the next one scheduled for 2020.
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