Any hope that a solution to the Northern Ireland protocol could be found ahead of the G7 summit have been dashed. This morning, David Frost – the minister in charge of Brexit relations – met with European Commission vice president Maroš Šefčovič at Admiralty House on Whitehall to discuss the current impasse over Irish Sea border checks.

The row? After the UK unilaterally extended grace periods on several checks, the EU has threatened to retaliate if the UK tries to extend these on imports of chilled meat products to Northern Ireland from Great Britain. This has led to talk of a ‘sausage war’ which threatens to cast a shadow over Boris Johnson’s attempt to woo world leaders, including Joe Biden in Cornwall on Thursday.

The meeting between Frost and Šefčovič failed to lead to much in the way of solutions. While Šefčovič said he remained ‘positive’ a solution could be found – he told hacks after the meeting had taken place: ‘Our patience really is wearing very, very thin, and therefore we have to assess all options we have at our disposal.’ Meanwhile, the UK side are taking heart simply from the fact that the two sides managed to agree to keep talking – rather than letting the confrontation spill out of control.

That may be enough to keep the issue under control when it comes to the G7 and Johnson’s first meeting with Biden, who is known to have strong feelings about the Good Friday Agreement. Ministers view it as an encouraging sign that Biden’s national security adviser Jake Sullivan told the BBC today that Biden will only tell fellow leaders at the summit that gains since the Good Friday Agreement must be protected. This is much less prescriptive than a statement in which Biden takes the EU’s side – a scenario that would worry the UK government.

However, even if Johnson gets through the summit without the issue blowing up, his problems aren’t about to go away. There is a fundamental disagreement between the two sides when it comes to a way through. The EU says that as the UK signed up to the protocol they must make it work. In response, the UK government argues it is unworkable and blames implementation on the EU side for making it even more difficult than it needed to be.

The preferred solution on the EU side is for the UK to align its agri-food standards as a temporary measure (on the basis that the UK could opt out if a trade deal came along that required divergence) but ministers worry this is a trap and would also send the wrong signal to countries they are currently in negotiations with.

As it stands, figures in Brussels are unsympathetic to the idea of fewer checks – as they worry it could set a bad precedent. Several EU diplomats see Frost as the problem – taking issue with his confrontational style. They hope that EU leaders could win Johnson over to their way of thinking. But for now this is wishful thinking – with the pair closely aligned in their approach. Or as the Prime Minister put it today at PMQs: ‘He is the greatest Frost since the Great Frost of 1709.’