British prime minister Boris Johnson has blamed the European Union for any customs checks that might be introduced on either side of the Border after Brexit. He said Britain was not proposing that there should be customs checks five miles from the Border but he said that some checks will be necessary.

“If the UK has to come out of the customs union – as it must and that’s the right thing for us to do, to actually take advantage of Brexit – then the whole of the UK has got to come out. And in those circumstances then the EU itself insists on some checks,” he told ITV News.

“What we are saying is those checks don’t need to take place at the Border, they don’t need to necessitate, they don’t need to involve new infrastructure, but you must, and this is where rubber hits the road. But you must have checks of some kind. They can be checks between importer and exporter, the expediter and the recipient. There are ways of managing it that don’t involve physical infrastructure and aren’t laborious.”

Mr Johnson said it would be preferable to have checks on goods moving across the Border in Ireland than creating a border in the Irish Sea by imposing checks on goods moving between Great Britain and Northern Ireland.

“Just to set this in context for you, it’s important to understand that trade North-South of the Border is dwarfed by trade East-West, from Northern Ireland to GB. So it would be wrong to, as it were, to keep Northern Ireland in a customs union with the EU and to create new checks down the Irish Sea for customs,” he told the BBC.

Mr Johnson is expected to describe in broad outline Britain’s proposal for an alternative to the backstop in his closing speech at the Conservative party conference in Manchester on Wednesday. The proposal will be presented formally in Brussels later this week.

Deal or no deal?

Mr Johnson said he thought the chances of agreeing a deal were good, despite his insistence that there must be two customs territories on the island of Ireland and that checks and controls will be required.

In an urgent question on the issue in the House of Commons on Tuesday, Labour’s Pat McFadden said that the European Union (Withdrawal) Act 2018 rules out regulations that “create or facilitate border arrangements between Northern Ireland and the Republic of Ireland after exit day which feature physical infrastructure, including border posts, or checks and controls” that did not exist before the day Britain leaves the UK.

“He has told us to discount reports from RTÉ overnight that suggest that the government were planning infrastructure a few miles from the Border. Would he regard such physical infrastructure a few miles back from the Border as incompatible with the legislation this House has passed?” he asked Brexit minister James Duddridge.

The minister declined to answer immediately, saying he would write to Mr McFadden.