The chances of a Jeremy Corbyn government are “slipping away” because he is “helping to facilitate a Tory Brexit”, a shadow minister says.

Clive Lewis, a Treasury spokesman, broke ranks to criticise the Labour leadership for its “dangerous” failure to oppose Theresa May’s exit plan full-on – warning it would keep the party out of power.

“My fear is that what we are now doing is that we are helping to facilitate a Tory Brexit,” he told a meeting of Labour supporters at the Commons.

Mr Lewis pointed to the fate of the Liberal Democrats, who were “comprehensively destroyed” for their part in delivering Conservative austerity, and warned Labour risked the same when Brexit backfired.

“The ramifications for our party will be severe,” he told supporters at a “Love Socialism, Hate Brexit” event.

“Just like the Liberal Democrats, once Theresa May has bogged off somewhere to go and put her trotters up, after she has delivered her Brexit, a new Tory leader comes in and says she was a disaster for this country, she betrayed this country – but so too did the leader of the opposition, he was part of this sorry debacle.

“It is us, the Labour party, who will pick up a lot of the flak for what happened.”

Insisting he and other pro-EU MPs were “loyal” to Mr Corbyn, and wanted to him lead “a Labour government”, Mr Lewis warned. “Our fear is that it’s slipping away.”

Top politicians' Brexit tweets haven't aged well Show all 18 1 /18 Top politicians' Brexit tweets haven't aged well Top politicians' Brexit tweets haven't aged well These billboards were plastered by campaign group Led By Donkeys @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well Undated handout photo issued by Led by Donkeys of their billboard featuring a blank tweet in Jeremy Corbyn's Islington North constituency in protest over what they claim is his lack of leadership on Brexit. PRESS ASSOCIATION Photo. Issue date: Tuesday February 12, 2019. For the past month, campaign group Led by Donkeys has been putting up posters all over the country featuring quotes mostly from hard-Brexit MPs which claimed the process of leaving the EU would be easy. The Labour leader is the group's latest target because of his failure to back a second referendum on Brexit. See PA story PROTEST Donkeys. Photo credit should read: Led by Donkeys /PA Wire NOTE TO EDITORS: This handout photo may only be used in for editorial reporting purposes for the contemporaneous illustration of events, things or the people in the image or facts mentioned in the caption. Reuse of the picture may require further permission from the copyright holder. PA Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter

The Tories were happy to “send the country to the wall” to achieve Brexit, he added. “It’s not the job of the Labour Party to help them do that. We should not be helping to deliver Brexit.”

Mr Lewis – who resigned to oppose the triggering of Article 50 exit notice in 2017 – again called for an in-or-out Final Say referendum on the prime minister’s deal.

He also warned of a future European war, as Brexit propelled the rise of the far right, saying: “If we walk away from Europe now, my children, your children, or possibly our grandchildren, will be back in Europe in a few years’ time – but in uniform.”

“We cannot forget what Europe has done to keep the peace in Europe.”

Two other frontbenchers – rail spokeswoman Rachael Maskell and Paul Sweeney, the shadow Scotland minister– also called for a referendum on the Brexit outcome.

Labour’s official position is still to press for a general election, if its softer Brexit plan is rejected in the Commons, with a fresh public vote only “an option”.

The criticism came as a Labour MP on the opposite wing of the party – Corbyn critic Chris Leslie – warned Final Say supporters were being “played for fools” by their leader.

The Nottingham East MP urged government ministers opposing Brexit to “do the brave thing and resign” to make up for the failure to deliver “what should be a solid Labour move against this outrageous situation”.

Criticising his party’s amendment, Mr Leslie said he no longer sees the “option of a public vote which was there when we had the amendment on 29 January”.

He added: “Why are we regressing in our party’s policy passed at the September conference?”

And he added: “I certainly feel that we are being played for fools by the leadership of the Labour Party on this particular issue because, by now, we should have reached the stage of a public vote when it comes to the option of remaining in the EU.”

Frontbench supporters of a referendum are becoming increasingly frustrated by Mr Corbyn’s failure to switch to outright support – even after the prime minster rejected Labour’s proposals, which include staying in a customs union.

Resignations are possible if the Labour leader continues to sit on the fence when the next round of Brexit votes take place on 27 February.