Boris Johnson hints at major Brexit climbdown with Northern Ireland customs union remarks

Prime minister risks fury of Democratic Unionist Party - and majority for any deal at Westminster - by refusing to say all of UK will leave trading bloc

Boris Johnson has hinted at a major concession to the EU to rescue a Brexit deal by refusing to say that Northern Ireland would leave the customs union.

In his first comments since an apparent breakthrough meeting with the Irish premier, the prime minister refused to discuss what compromises he had agreed to make.

Instead, Mr Johnson simply insisted he had given away “nothing that will damage the ability of the whole of the UK to take full advantage of Brexit”.

“It would be wrong of me to give a running commentary on the negotiations. Let negotiators get on with the job,” he told broadcasters.

The evidence of a looming climbdown is already triggering Unionist anger. Jim Nicholson, a former Ulster Unionist MEP, said he feared Northern Ireland was about to be “offered up as a sacrificial lamb”.

It is believed that Mr Johnson is trying to resurrect a version of Theresa May’s doomed ‘customs partnership’, which would see Northern Ireland effectively remain in the EU customs union – but still be included in UK trade deals.

Embarrassingly for Mr Johnson, when his predecessor floated the idea last year, he branded it “a crazy system whereby you end up collecting tariffs on behalf of the EU at the UK frontier”.

There may also be a legal barrier to a U-turn after the hardline European Research Group successfully passed an amendment, in the summer of 2018, preventing a different customs arrangement for Northern Ireland.

Jacob Rees-Mogg, then head of the ERG – but now Commons Leader and a key Johnson ally – said, of the partnership proposal: “It’s completely cretinous, the silliest thing I could possibly think of, it’s a betrayal of good sense.”

The EU also demolished the idea when it threw out Ms May’s so-called Chequers Plan, saying it would never “delegate the application of its customs policy, of its rules, Vat and excise collections to a non-member”.

Under the plan, the UK would collect tariffs on goods coming into the UK on behalf of the EU. If those goods remained in the UK – with lower tariffs – companies could then claim back the difference.

The new version would, it appears, apply to Northern Ireland only, creating an administrative barrier in the Irish Sea.

Mr Johnson himself urged caution, adding: “I had a good conversation with the Irish Taoiseach Leo Varadkar yesterday and I think both of us can see a pathway to a deal, but that doesn't mean it's a done deal.”

Meanwhile, key manufacturers have warned of a “serious risk” in Mr Johnson’s new proposals, which also break with Ms May by planning to diverge further from EU arrangements.

The bodies representing carmakers, chemicals, the food and drink industry, aerospace, and pharmaceutical – 1.1m workers in total – fear rising costs if the UK quits the relevant EU agencies.

Significantly, the organisations had previously criticised only the risk of a no-deal Brexit, having accepted Ms May’s withdrawal agreement.