The latest round of talks between the two sides to rehash post-Brexit trade arrangements for Northern Ireland are due to begin in London on Friday.
There is growing speculation that the UK is poised to use a get-out clause in the coming weeks by triggering Article 16 to suspend arrangements agreed in the Northern Ireland Protocol.
Mr Sefcovic is set to tell Lord Frost that his demand to cut out the role of European Court of Justice (ECJ) judges in the arbitration process cannot be met.
“The UK wants us to engage in intensive talks and we are happy to do so,” said an EU official. “But then the UK must take a step towards us to ensure that the talks are meaningful.”
The official added: “On questions around governance and the court of justice we have always made clear that we think that the objectives set out by the UK are unattainable.”
The protocol effectively keeps Northern Ireland inside the EU’s single market for goods, resulting in some checks for products crossing the Irish Sea from Great Britain.
In October, the EU offered a series of changes to the protocol, which would remove 80 per cent of checks on goods between Northern Ireland and the UK mainland.
Lord Frost said on Wednesday that triggering Article 16 – which would effectively suspend elements of the arrangements – would be the only option if the EU did not move further on UK demands.
The Brexit minister there was “a real opportunity to turn away from confrontation, to move beyond our current difficulties and put in place a new, and better, equilibrium” in the talks.
He added that it was “not inevitable” that Article 16 would be triggered. Lord Frost said: “In my view, this talks process has not reached its end … If, however, we do in due course reach that point, the Article 16 safeguards will be our only option.”
Irish minister for European affairs Thomas Byrne has said a “tough guy” approach to talks when it comes to Northern Ireland will lead to “disaster”.
Asked on BBC Radio 4’s Today programme if there is a serious danger of a full-scale trade war, Mr Byrne said the EU is in “solutions mode”, adding: “A tough approach, or a tough guy approach, when it comes to Northern Ireland can only be counter-productive and will lead to disaster.”
He said he is “very glad despite that gloomy atmosphere” that there are talks taking place on Friday, adding “there is a prize of stability and peace in Northern Ireland”.
The Irish government has held talks with US president Joe Biden’s administration about the protocol. On Thursday, Irish foreign minister Simon Coveney said contact with the US government was designed to “encourage progress” in negotiations.
Meanwhile, Irish deputy premier Leo Varadkar has warned that retaliatory action from the EU should be expected if the UK activates Article 16, amid fears a trade war between the two sides could break out in the months ahead.
Register for free to continue reading
Registration is a free and easy way to support our truly independent journalism
By registering, you will also enjoy limited access to Premium articles, exclusive newsletters, commenting, and virtual events with our leading journalists
Already have an account? sign in
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies