Unionist group says DUP tests not met as former Prime Minister Johnson critical of Windsor framework
Boris Johnson who brokered the Northern Ireland Protocol deal with the EU has said Rishi Sunak's Windsor Framework would be "very difficult" to vote for - despite appearing to take some of the credit for the deal.
The former prime minister was critical of the agreement saying it was not about the "UK taking back control".
He also said he hoped the DUP would return to power sharing.
Mr Johnson also conceded he had made mistakes in brokering the protocol saying it was "all my fault, I fully accept responsibility".
It comes as a unionist think tank said the Windsor Framework does not strengthen the constitutional status of Northern Ireland as part of the UK - indicating it does not meet the DUP's tests for restoring power sharing.
The criticism was made by former Northern Ireland attorney general John Larkin KC in the new report.
DUP MP Ian Paisley contributed the foreword for the report in which he said his instinctive reaction was that the new deal agreed between the UK and the EU does not solve the problems of the Northern Ireland Protocol.
In a Westminster speech, Boris Johnson criticised the new deal.
He said: "I believed we should've done something very different. No matter how much plaster came off the ceiling in Brussels.
"I hope that it will work and I also hope that if it doesn't work we will have the guts to employ that (Northern Ireland Protocol) Bill again, because I have no doubt at all that that is what brought the EU to negotiate seriously."
He added: "I'm conscious I'm not going to be thanked for saying this, but I think it is my job to do so: we must be clear about what is really going on here.
"This is not about the UK taking back control, and although there are easements this is really a version of the solution that was being offered last year to Liz Truss when she was foreign secretary.
"This is the EU graciously unbending to allow us to do what we want to do in our own country, not by our laws but by theirs."
Mr Johnson conceded he made mistakes in signing his Northern Ireland Protocol that caused the DUP to walk out of power sharing because of trade barriers in the Irish Sea.
"I thought those checks would not be onerous since there isn't that much stuff that falls into that category; most of the goods stay in Northern Ireland," he said.
Muttering, the former prime minister added: "It's all my fault, I fully accept responsibility."
The Windsor Framework was announced on Monday following months of talks. It seeks to remove post-Brexit trade barriers, creating a new system for the flow of goods into Northern Ireland.
The new report by the Centre for the Union Constitutional Studies Group has been co-authored by loyalist activist Jamie Bryson.
The report states: "We cannot recommend, in the absence of additional components being added to the framework, alongside some present elements being amended, unionist support for the Windsor Framework."
In his foreword, Mr Paisley said: "It is my view that unionism will have to dig deep in the coming days to overcome the problems caused by the protocol.
"My instinctive reaction to the Windsor Framework remains that the problem is not yet solved."
He added: "I am clear from what I have read and heard since 27th February that as Ursula von der Leyen stated, the European Court of Justice is the 'sole and ultimate arbiter of EU law' and it will have the final say on all matters of EU law.
"Given that the Windsor Framework will not be legislated for, it is clear that Northern Ireland will remain in a very different position from the rest of then UK."
Mr Larkin was asked to give a legal analysis on the provisions of the new framework.
He concluded: "Are the proposals contained within the Windsor Framework compatible with the Acts of Union 1800, particularly Article VI thereof? No.
"Do the proposals contained within the Windsor Framework remedy the "subjugation" of Article VI of the Acts of Union 1800? No.
"Do the proposals in the Windsor Framework strengthen the constitutional guarantee respecting the constitutional status of Northern Ireland? No."
Mr Larkin was the barrister who represented a unionist collective in an unsuccessful legal challenge to the protocol which was heard at the UK Supreme Court.
The DUP, which is currently boycotting the Stormont power-sharing institutions, has said it will study the new framework before giving its verdict.
However, a number of party members have already expressed concerns. Lord Dodds has said he does not believe the new arrangements would remove the trade border in the Irish Sea.
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