Sir Jeffrey Donaldson has warned checks on goods coming from Great Britain to Northern Ireland may be suspended by his Stormont ministers if changes to the protocol are deemed “unacceptable”.
The DUP leader told The Times his party was “not going to be in the business” of implementing the protocol, while he warned the Irish government the Good Friday Agreement was at risk if a satisfactory deal on the issue cannot be reached.
The Lagan Valley MP also told the newspaper he wants to “broaden the appeal of unionism” around social issues such as gay marriage and said his party must be “inclusive”.
On Thursday the EU chief Ursula von der Leyen rejected a call to renegotiate the post-Brexit deal on Northern Ireland during a phone call with Boris Johnson.
The European Commission president said on Thursday that Brussels will “be creative and flexible” over the Northern Ireland Protocol “but we will not renegotiate”.
The Northern Ireland Protocol is a section of the Brexit deal designed to avoid border checks on the island of Ireland.
The trading arrangements impacting goods moving between GB and NI have caused significant tension in unionist and loyalist communities, who argue the checks damage the constitutional integrity of the region within the UK.
On Thursday, the Grand Orange Lodge in Ireland said the organisation would be meeting in the coming weeks to “endorse any agreed action by the Unionist community” around the protocol, adding they would “not be found wanting” on defending the Union.
Sir Jeffrey said a compromise on the arrangement was possible and argued the Northern Ireland Executive should be included in talks between London and Brussels.
He added that the party would not be taking Boris Johnson on “trust alone”, after the DUP was scarred over the Prime Minister’s previous assurances there would not be an Irish Sea border.
The DUP has set out seven tests which they say will need to be passed if the party is to support any post-Brexit arrangement.
Sir Jeffrey said if the tests are not met, relationships both North-South and East-West will be damaged.
“Those seven tests are all based on commitments that the government has made itself,” he told The Times.
“If the government doesn’t live up to those commitments and if the outcome fails to remove the Irish Sea border then... there is no way we can work and co-operate on a North-South basis when the Irish government and the EU are undermining our relationship with Great Britain.”
Meanwhile, the DUP leader said it was his job to move the party back to the centre ground when it comes to social issues.
At the start of July Sir Jeffrey acknowledged past comments made by members of his party had been “hurtful” to LGBT people here.
However, the leader was accused by opponents of qualifying his apology, after also referring to comments made towards those “from a strongly held faith perspective”.
Sir Jeffrey Donaldson told The Times: “We need to make clear that unionism is inclusive.
“We need to look at the language that’s used at times when we discuss what are very sensitive social issues.”