The “bizarre” situation of some politicians defending the Northern Ireland Protocol has been likened to Belfast masochists defending Brussels sadists.
Christopher Stalford criticised parties who he said were standing by arrangements that will impose additional costs on families and firms here.
His comments came during questions to Economy Minister Diane Dodds at the Assembly.
Mr Stalford said: “Does she agree that what we are dealing with here is a group of Belfast masochists defending Brussels sadists?”
It drew laughs from MLAs.
Mrs Dodds responded: “That is quite the description. What we have here is an attitude of burying your head in the sand.”
Earlier, Ms Dodds denied “political stunts” over her party’s refusal to engage with the Irish Republic over the protocol.
The DUP said it wants to send a “strong signal” to the Irish Government by stopping north-south activities related to the protocol.
The plan was announced amid what the party has termed the “growing crisis” over post-Brexit arrangements.
The protocol is the mechanism by which a hard border is avoided on the island of Ireland.
It requires regulatory and customs checks on goods moving from Great Britain to Northern Ireland, effectively creating an Irish Sea border.
But unionists say it has driven an economic wedge between Northern Ireland and the rest of the UK.
Mrs Dodds said she has “made clear that at all times she will act in the interests of the people of Northern Ireland and our local economy”.
“We have indicated to our own Government that they need to act, but we also need to send a message to the Government of the Irish Republic that north/south relationships are also impacted by the implementation of a protocol for which they are cheerleaders and which does real damage to the agreements they purport to uphold, along with the real damage it does to our businesses, consumers and communities here in Northern Ireland,” she told MLAs.
“We can and we will not continue to act as though relationships have not been impacted by their actions. We will consider each matter on its merits, not doing anything of course that negatively impacts on Northern Ireland, but it cannot be business as usual for north/south relations because of the issues that flow from the protocol.”
There was a sharp exchange over the approach between Mrs Dodds and Sinn Fein MLA Caoimhe Archibald.
Ms Archibald accused the minister of “engaging in silly political stunts”.
But Mrs Dodds hit back: “I am not in the position of stunts and if I was I need only to look at the party opposite ... if there are stunts in this house this party has the monopoly on them.”