SDLP MP Claire Hanna has said that "if the DUP refuse to do power sharing, they needn't think that they can return into the comfort of one sided direct rule".
She was speaking to UTV's View From Stormont.
Meanwhile, veteran Conservative MP Bill Cash has said the ERG's view on the protocol is in line with that of the DUP's.
The ERG are a collection of Conservative MPs known as the European Research Group, who are pro-Brexit and vocally opposed to the Northern Ireland Protocol.
He added he "really does believe very strongly that it is the EU that are insisting on these borders and border posts in a way that is completely unacceptable and unnecessary".
"I don't think there's any other democratic country in the world which has got an arrangement whereby part of its territorial and constitutional jurisdiction is decided by another country, and that is the EU in this case".
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