FORMER deputy prime minister Nick Clegg is returning to front-line politics as Lib Dem spokesman on the EU.

The ex-MEP insists that turmoil in the Labour Party means no one is holding the Government to account on Brexit.

Mr Clegg, who quit as Lib Dem leader after the party's near wipe-out in the 2015 general election, expressed alarm at widespread confusion regarding the implications of Brexit.

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He said: "Theresa May says Brexit means Brexit, but no one actually knows what that means. Will we be in the single market or cut off from it, with all the implications that has for British jobs and our economy?

"What does it mean for immigration? What about the Brits who live abroad and the Europeans who have made our country their home? How will we co-operate with our neighbours to tackle terrorism, cross-border crime and climate change?

"With no meaningful opposition from the Labour Party, no exit plan from the Government, Whitehall unprepared for the Brexit negotiations, and above all, Theresa May's refusal to seek a mandate from the people for what is in effect a new government, there is a real risk that she and her Brexit ministers won't be subject to the scrutiny and accountability which voters deserve.

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"Whatever your views on Brexit, it is in everyone's interest to make sure what happens next is debated openly and scrutinised properly.

"So I want to make clear that we will work openly and collaboratively with people of all parties and who believe that Britain must remain an open economy and a tolerant, outward-looking nation."

Lib Dem leader Tim Farron said his predecessor is in a unique position to challenge the Government as he sat around the Cabinet table with key Tory players in the coalition years.

He added: "There is no-one better placed in British politics to hold the Government to account over Brexit than Nick.

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"When it comes to facing down Theresa May - whether it's over the Snooper's Charter, immigration and loads of other issues they crossed swords over in government - Nick has been there and got the T-shirt.

"No one is better placed than Nick to challenge Theresa May, Boris Johnson, Liam Fox and David Davis. I'm proud to have him by my side as we lead the Lib Dem fightback in the months ahead."