Lord Frost was accused of using an unassailable “red line” to create a “destabilising stand-off” with Brussels amid indications the Government was edging closer to overriding parts of its own post-Brexit agreement.
The Tory peer will use a speech in Portugal on Tuesday to say the EU must go further than scrapping its prohibition on British sausages crossing the Irish Sea.
He will call for “significant” changes to the protocol he negotiated, including over the role of the European Court of Justice (ECJ) in governing the arrangements in Northern Ireland.
“Without new arrangements in this area, the protocol will never have the support it needs to survive,” he is expected to tell the diplomatic community in Lisbon.
But Ireland’s foreign minister, Simon Coveney, questioned whether UK ministers “actually want an agreed way forward or a further breakdown in relations?”
He argued on Twitter that the Government is creating a “new ‘red line’ barrier to progress” which ministers are aware the “EU can’t move on”.
Lord Frost replied that the issue of the ECJ “is not new”, adding: “The problem is that too few people seem to have listened.”
Shadow Northern Ireland secretary Louise Haigh accused the Brexit minister of seeming “more interested in political posturing than making his own deal work”.
“People and businesses in Northern Ireland are sick and tired of the endless threats and uncertainty from a Government they have long since lost trust in,” the Labour MP added.
“They want to see urgent solutions, not another destabilising stand-off. The Government should stop posturing and get the job done.”
Lord Frost’s speech will come a day before the EU is expected to produce plans to resolve issues with the protocol, which has led to economic barriers between Northern Ireland and Britain.
Brussels is likely to propose that chilled meats can continue crossing the Irish Sea from Britain after the end of the current grace periods, in a move to alleviate the so-called sausage wars.
But Lord Frost is expected to double down and say: “The commission have been too quick to dismiss governance as a side issue. The reality is the opposite.
“The role of the European Court of Justice in Northern Ireland and the consequent inability of the UK Government to implement the very sensitive arrangements in the protocol in a reasonable way has created a deep imbalance in the way the protocol operates.”
A Government source threatened that the UK would trigger Article 16 of the protocol – effectively overriding parts of the deal – if the EU proposals amount to “tinkering around the edges”.
The protocol was negotiated to avoid a hard border with Ireland, by effectively keeping Northern Ireland in the EU’s single market for goods.
But unionists have been pressuring for it to be scrapped because of the trade barriers it has created on products crossing the Irish Sea from Great Britain.
Lord Frost will also this week share a new legal text with the European Commission to propose the “foundation” for a new protocol to support the Good Friday Agreement.
