To prevent the creation of a new centre party Corbyn must oppose Brexit

A new anti-Brexit centre party is not going to be launched anytime soon, despite Friday’s explosive claim by James Chapman, the former chief of staff to David Davis, that two current cabinet ministers, and some former Conservative ministers and senior Labour figures are sympathetic to the idea.

We should certainly take seriously Chapman’s view that Brexit will be a “disaster” because he has seen the Government’s preparations – or lack of them – up close. Plenty of civil servants share his view; some even tell their ministers. So there is a case for a new party when a right-dominated governing party and left-wing opposition appear to conspire in an economically-dangerous hard Brexit outlined by Theresa May in January. That leaves some politicians homeless; they are convinced many voters feel the same, even though 82 per cent of people voted Conservative or Labour in June.

Although there is chatter at Westminster about a new party, that doesn’t mean it will lead anywhere. A band of about 20 pro-Europe Tory backbenchers are talking to like-minded Labour and Liberal Democrat MPs about amending Brexit legislation. But are Tory backbenchers and cabinet ministers really going to jump ship, and risk handing Jeremy Corbyn the keys to Downing Street? I doubt they would have the stomach to face charges of betraying their party. As one put it: “We are Conservatives first, and pro-Europeans second.” Breaking up is hard to do.

Similar calculations take place in Labour circles. The Democrats, the new party envisaged by Chapman, would require a sizeable breakaway from Labour MPs to be credible. That might well have happened if Labour had done badly at the June election and the left had retained the leadership. There was no shortage of rich financial backers for the project. But Corbyn’s brilliant campaign and the strength of the Labour brand mean that even his harshest critics are keeping their heads down, burying themselves in their work as MPs rather than plotting a new party. “If we break away, or even talk about it, we would be blamed forever by the left for Labour not winning when it was on the brink of power,” said one Labour MP.

Some Corbynistas fret about a new party – not because they fear those they erroneously brand “right-wingers” would sweep the country, but because the Social Democratic Party walkout in 1981 split the anti-Tory vote and helped Margaret Thatcher win the following two elections.

Those who dare to dream about a new anti-Brexit party point out that politics is much more fluid now than in the 1980s. Last year’s referendum has eroded voters’ class-based, tribal party loyalties. Under their new leader Vince Cable, the Lib Dems would probably be more open to joining the party than previously.

Backers look with admiration across the Channel at the rise from nowhere of Emmanuel Macron and En Marche! But, when pushed, they cannot answer the big question: who is our Macron? They had one once – Tony Blair. Instead of launching a new party, he mounted a take-over of Labour – a feat now repeated by Corbyn. Blair would be among the first to sign up to a new party. He wants his Institute for Global Change to “remake the centre left”. But he cannot lead a new party as he has too much Iraq baggage. David Miliband blows hot and cold about returning to British politics from New York, but re-entry is never easy once you have left the Commons.

However, there are some circumstances in which a new party could yet happen. A bad Brexit deal could be the catalyst for pro-European MPs across parties to vote for a second referendum. A realignment for a final campaign to stop Brexit might then take place. True, the Chancellor Philip Hammond’s success in pushing the Cabinet towards a smoother exit will make Tory MPs less likely to walk out on their party. But the proposed transitional deal also gives opponents of Brexit up to three years for public opinion to change, a necessary ingredient for them to succeed.

Corbyn stopped a new party being formed by doing so well in June. He could stop it again. Firstly, by bowing to the growing pressure from Labour MPs for stronger opposition to May’s Brexit. Secondly, by preventing a Labour civil war and putting out the word that his followers should not deselect Corbyn-sceptic MPs, who might be tempted by a new party if they were sacked. Neither action will come naturally to Corbyn but if he doesn’t bite the bullet, we could have a new political landscape in a few years.

Brexit is a unique issue that cuts across the battle lines between and within parties. It has the potency to suspend the normal rules of politics and, crucially, to persuade politicians to put country before party. One former Cabinet minister, who would join a new centre party said: “It’s not dead, just in abeyance. It all hinges on Brexit.”