Clegg speaks about Brexit in the run-up to the U.K. snap election, May 2017 | Andy Rain/EPA EU CONFIDENTIAL Nick Clegg backs ‘constitutional crisis’ to halt Brexit Former UK deputy PM goes to Brussels to accuse ‘muppet’ government in London of ‘cluelessness.’

British MPs should vote to reject the government's final Brexit plan when it comes to a vote later this year — even though that will trigger a constitutional crisis, former Deputy Prime Minister Nick Clegg said.

Speaking to POLITICO's EU Confidential podcast in Brussels this week, the former Liberal Democrat leader also attacked Prime Minister Theresa May's Cabinet, describing its ministers as "muppets" who had destroyed the British government's reputation for competence.

Pro-Brexit MPs have argued the British parliament should approve whatever deal May strikes with the European Union over Brexit as to do otherwise would go against the will of the people expressed in the 2016 EU referendum.

But Clegg said MPs have every right to vote down the government's legislation as it was clear that none of the promises made by Brexit campaigners would be realized.

"When it becomes obvious — as it already has — that the British people are not going to get any, I mean literally none, of that great long list of beguiling promises they were made by the Brexiteers, I think they are totally within their rights to say 'well, hang on a minute, we're not going to vote for this because this is not what you told our constituents they were going to get,'" Clegg said.

"At that point, of course, you'll have a crisis, there will be a standoff between parliament and government — a kind of constitutional crisis, if you like," Clegg said.

He said it would then be important for both the U.K. and the EU to take time out to consider their next moves, which would mean finding a way to stop the clock ticking toward Britain's exit from the bloc at the end of March 2019.

"I do think at that point it will be essential, one way or another to play for some time," he said.

"Everyone just needs to calm down a bit and people need to catch their breath," Clegg said. "You can do that in different ways ... The 27 [other EU] countries, obviously at the behest of the United Kingdom, could just extend the existing Article 50 timetable. I suppose you could find some kind of way of basically withdrawing the Article 50 letter pending the ability of another British government to retable it again ... I mean, a lot can be done by consensus."

"Jacob Rees-Mogg is like a Don Quixote in pinstripes" — Nick Clegg

Clegg, who was previously also a European Commission official and member of the European Parliament, accused British ministers of "cluelessness."

"I think is impossible exaggerate the level of a cluelessness and incompetence now at the heart of British government," he said. "I think it's really difficult for folk here in Brussels and in other European capitals to get used to the idea that, you know, to all intents and purposes, the British government now looks like a bunch of muppets sitting around the Cabinet table."

He also took aim at leading Brexiteers such as Conservative MP Jacob Rees-Mogg.

"He's like a Don Quixote in pinstripes ... rushing at windmills that don’t kind of exist," Clegg said. "They're like Maoist revolutionaries — they don't care how many bodies they sacrifice along the way or how much hardship is inflicted on people in the long march."

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