Could Boris Johnson scupper Rishi Sunak’s Brexit plans?

Boris Johnson desperately wants to be prime minister again and is willing to use the latest Brexit row in his effort to undermine Rishi Sunak. So says former Tory chancellor George Osborne.

It’s a cynical interpretation. But when it comes to Johnson, it pays to be cynical. The idea that the former prime minister is looking out for his own interests is almost always the safest bet when it comes to scrutinising his motivations.

A source close to Johnson has let it be known that he thinks it would be a “great mistake” to drop the Northern Ireland Protocol Bill – the one that would unilaterally override customs checks and potentially spark a trade war with Brussels.

Cue an almighty tizzy, with Tory Brexiteers backing Johnson to the hilt and Tory moderates accusing him of “treachery”. Osborne thinks Johnson will use any instrument to bring down his enemy in No 10, adding: “If the Northern Ireland negotiations are that instrument, he will pick that up and hit Mr Sunak over the head with it.”

The Johnson intervention certainly comes at a crucial and delicate time. Sunak is thought to be on the verge of finally agreeing a resolution with Brussels to end the protocol dispute.

It is assumed that if a deal is done, then the Sunak government will quietly ditch the protocol bill. But the DUP and the European Research Group (ERG) want No 10 to back out of the negotiations and push on with the unilateral plan, however unrealistic it may be.

Johnson appears to be signalling to his old buddies that he remains one of them and that they have every right to oppose the deal – “winding up” the unionists, in the words of one government insider.

Could the former PM really be powerful enough to scupper a deal? Probably not. But he can cause a bigger and more damaging mess than is strictly necessary.

It is not yet clear whether any compromise deal forged by Sunak will be put to a vote in parliament – but the ERG has warned of a major Tory rebellion if it comes to the Commons.

Keir Starmer has made clear that Labour will back a sensible compromise. It is thought that a deal agreed by Sunak would involve a green lane to reduce checks on goods not intended for export beyond Northern Ireland, along with a reduced role for the European Court of Justice in Brexit-related disputes.

Even if there is little chance of a deal failing to pass, Sunak could be weakened by relying on Labour to get it through parliament. As Johnson ally James Duddridge told The Independent at the weekend, Sunak doesn’t have “vast amounts of cash in the bank of goodwill” with his own backbenchers.

The PM also has very little goodwill with the DUP, who look certain to reject the deal and refuse to restore the Stormont institutions.

In the vain hope that the unionist party will decide to resume power-sharing in the months ahead, Sunak may be forced to tell them that he will keep the “nuclear option” of the protocol bill in his back pocket.

It’s still there in the Lords, the PM might say, waiting to be activated if the deal that the negotiating teams from London and Brussels appear to have reached fails to work out as planned in the months ahead.

But a desperate ploy such as this would amount to failure. A deal was supposed to draw a line under the whole mess, and allowing the dissatisfaction of the DUP and Brexiteers to fester and grow will only defer the argument to a future time.

The art of getting Brexit deals done has previously involved keeping different parties and factions on board by telling them what they want to hear. But the same approach has led to those deals coming undone very quickly. Something that Johnson should know all too well.