And before EU-UK relations can be reset, Mr Sefcovic will demand reassurances from Ms Truss that she will not renege on the terms of any deal on the province.
“We need to rebuild trust and this is done through respecting our agreements, which have only recently been signed and ratified,” an EU official told the Telegraph.
Under the protocol, Northern Ireland continues to follow some EU Single Market rules to prevent a hard Irish border, and British imports face checks to ensure they meet EU standards, which has created a trade border in the Irish Sea.
The UK argues the trade checks – which Unionists have denounced as driving a wedge between Northern Ireland and the rest of the UK – are having a chilling effect on trade.
In October, the EU offered to remove up to 80 per cent of the checks in return for bolstered market surveillance.
Talks to cut red tape resumed this week, without any significant breakthrough expected by officials on both sides.
Officials close to the talks described the long-running stand-off as another “Groundhog Day” in the Brexit negotiations.
They said that Britain’s negotiating position has not changed since Ms Truss took over from Lord Frost, who quit Cabinet last month in anger over Covid measures.