Momentum is building for a so-called “people’s vote” after a £100,000 surge donations after Theresa May’s Brexit deal was crushed in parliament. 

A total of £100,308 was handed to the official People’s Vote campaign in the 20 hours following the Prime Minister’s defeat on Wednesday.

The cash was made up mostly of small donations – the largest donation was £500 while the average was £25 – and campaign chiefs claim it underlines a shift in public opinion on a re-run of the Brexit vote.   

The news came as Jeremy Corbyn was under fresh pressure to add Labour’s weight to the drive after May’s government comfortably survived his motion of no-confidence on Thursday night. 

Plaid Cymru, the Greens, the SNP and the Lib Dems published a joint letter  saying they would not back “meaningless” repeated attempts to force a general election that add to the Brexit “logjam” in Westminster. 

Corbyn should instead switch position and back a second referendum, they demand.

HuffPost UK also understands pro-second referendum Conservatives were due to make public a Tory “people’s vote” campaign on Thursday. 

A cross-party group of MPs, however, have been meeting to discuss pushing for a Norway-style Brexit after moves by former Tory minister Nick Boles.

Labour, meanwhile, repeated its demand for May to back a permanent customs union and rule out no-deal after the PM pledged to hold talks with other parties. 

Second referendum backers insist both plans will fail and Corbyn’s support would make their cause irresistible.

James McGrory, director of the People’s Vote campaign, said: “We have been overwhelmed by the generosity of the thousands of people who have dug deep to give whatever they can to support the push for a people’s vote,” he said. 

“By giving even just small amounts, the support we receive means we can put on rallies, advertise on social media and on leaflets and keep up the momentum for a people’s vote.”

The appeal will have been boosted by television coverage of a mass rally outside Westminster on the night of the Brexit deal vote. 

Anna Turley MP, a leading supporter of the campaign said “momentum is building across the country”, adding: “Parliament is gridlocked and a people’s vote is the only way forward out of this Brexit mess.

“So it’s heartening to see countless numbers of people donating money, marching, rallying, writing to their local MP and campaigning in their communities up and down the country in support of securing a people’s vote on Brexit.” 

May has said her government had “a responsibility to identify a way forward” on Brexit, adding she would meet with senior MPs from all parties.

Green MP Caroline Lucas said it would be “unconceivable” for Labour to enter into such talks. 

Labour MP Paul Williams, meanwhile, called for all non-Brexit parliamentary business to be suspended. 

“There is nothing else more important than sorting this out,” he said. “I don’t think the public will understand why we are debating other stuff. 

“We should put deadlines on this process and if that means sitting at weekends then so be it. 

“By the end of the month, we need to provide businesses with certainty.” 

Plaid Cymru’s Westminster leader Liz Savile-Roberts, who co-ordinated the cross-party call for Labour to back a Brexit vote re-run, said: “Meaningless motions of no confidence tabled by the Labour Party on a rolling basis will do nothing but worsen the logjam and create further economic distress.

“We will not support efforts that only run down the Brexit clock – they must present a real chance of breaking the deadlock.” 

Williams, who also supports a second referendum, said he believed it to be a matter of time before the idea had a majority across parliament.  

“There are some MPs who want to try out some other options first but the problem with that is that we are massively running out of time,” he said.   

Plans for a soft Brexit would not succeed, Williams claimed. 

“I’m almost certain that it will fail,” he said.“It would be an establishment stitch-up. It would be a very small number of elite MPs getting together in a room, coming up with this plot to stay close to the EU and it is so out of touch. 

“We do need to reach out and see if there is a position that all MPs will back, but I think this process needs to happen within days not weeks.” 

There was also speculation on Thursday night that Labour could be facing frontbench resignations.  

Williams added: “I don’t think Jeremy Corbyn will whip for [a soft] Tory Brexit because I don’t think trade unions will back it. Trade unions want Labour MEPs in parliament arguing for better rights for British workers.”