The Liberal Democrats have ordered 90 camp beds so that their peers can stay overnight in Parliament in a bid to thwart Theresa May’s Brexit plans.

The party is preparing for a late-night stand-off with MPs as they seek to scupper the Brexit Bill, which gives the Prime Minister authority to begin leaving the EU.

Mrs May is determined to push ahead with triggering Article 50, which starts the process of quitting the EU, in the next few weeks despite the Lords inflicting her first parliamentary defeat over Brexit on Wednesday night.

Mrs May is determined to push ahead with triggering Article 50, which starts the process of quitting the EU, in the next few weeks

But she could face a Tory rebellion in the Commons that ties her hands in negotiations – and a final push by the Lords to cause problems.

Ministers hope MPs will strip out any amendments added by the Lords to dictate the terms of Brexit when the Bill returns to the Commons on March 13.

The Lib Dems yesterday held urgent strategy talks to discuss how they hope to retain these changes in a stand-off between the Lords and the Commons.

Baroness Smith of Basildon, the Labour leader of the Lords, has said peers are unlikely to fight further if MPs vote down their amendments.

But the Lib Dems hope to persuade pro-Remain peers to help them ‘ping-pong’ amendments between the houses. Despite having just nine MPs, the party has 102 unelected peers in the Lords.

Some 90 folding beds have been ordered by the party in preparation for all-night sessions so they can be ready to vote at any point during the night. The peers will camp out in their offices.

A party strategist said: ‘We are planning for every eventuality and preparing for all-night sessions. If that means pizza and food delivery at 3am then so be it. We have plans in place for sleeping bags and beds for our peers.

‘We think this matters and [Lib Dem leader] Tim Farron has said we will go through the lobbies time after time to defend the rights of 3.3million EU nationals who live and have made their home here.

A party strategist said Lib Dem leader Tim Farron (pictured) plans to 'go through the lobbies time after time to defend the rights of 3.3million EU nationals'

'We are also committed to fighting tooth and nail to give the people a final say on the deal.’

Tory MP Andrew Rosindell accused the Lib Dems of desperation, saying: ‘It seems they will go to any possible length to undermine the democratic wishes of the people … This is all unnecessary as the British people have voted in a referendum that we should leave the EU and the House of Commons has backed invoking Article 50.

‘I don’t see what the Liberal Democrats think they are achieving … many on the Remain side now want this matter to be got on with and not dragged on any longer. It looks like they are desperate.’

Peers voted on Wednesday to amend the Bill, to force the Government to guarantee unilaterally the post-Brexit rights of 3.3million EU citizens living in the UK – even though the EU has refused to discuss the rights of 1.2million Britons living in other member states.

Ministers made clear their intention to overturn the vote when the legislation goes back to the Commons this month.

Some 90 folding beds have been ordered by the party in preparation for all-night sessions so they can be ready to vote at any point during the night. The peers will camp out in their offices

But they face the prospect of a second defeat in the Lords next week on another opposition amendment, which would require Parliament to be given a ‘meaningful’ vote on Britain’s final withdrawal.

The Government has promised a vote on any agreement with the EU, but opponents fear that if there is no deal the UK will simply leave, without Parliament able to intervene.

The amended Bill will go back to the Commons on March 13-14, when ministers are confident MPs will remove the amendment on EU citizens living in the UK. But pro-Remain Tories could join Labour and the Lib Dems to support the amendment on a ‘meaningful’ vote.

When MPs voted on a similar amendment last month it was rejected by a majority of 33, with seven Tory MPs rebelling.

Europhiles believe that if it returns to the Commons, MPs could be emboldened by the defeats in the Lords and more pro-Remain Tories could be persuaded to rebel.