There will be no business as usual for the Stormont Executive until concerns over the Northern Ireland Protocol are tackled, Sir Jeffrey Donaldson has said.
The DUP leader also expressed disappointment in the lack of action from the UK Government on the post-Brexit mechanism.
The protocol prevented a hard border on the island of Ireland after Brexit, but is deeply unpopular with unionists because it introduced new trade barriers in the Irish Sea between Northern Ireland and the rest of the UK.
While the EU has given concessions on its operation, notably to ease the flow of medicines, these have not satisfied many who oppose it.
The DUP escalated their protest against the Northern Ireland Protocol last month with the resignation of First Minister Paul Givan, which also removed deputy First Minister Michelle O’Neill from the joint office.
While the other ministers remain in post, the Executive cannot function fully.
The Assembly is set to be dissolved later this month for fresh elections.
But Sir Jeffrey said he wants to see action on the protocol before a fully functioning Executive can return after the election.
Political talks are expected to follow the poll to restore the Executive.
“Of course I want to see a fully functioning Executive. I’m very clear about what needs to happen for progress to be made,” Sir Jeffrey said.
“I’m disappointed that the Government haven’t yet taken the action that they said they would take in New Decade New Approach Agreement, to protect our place in the UK internal market.
“And until they do that it will not be business as usual in the Executive because we are being asked to implement the protocol, which is harmful to Northern Ireland, harmful to our economy, harmful to the people that we represent and that is not sustainable.”