Leading conservative and pro-Brexit think tanks have called on MPs to vote against Boris Johnson’s “defective” withdrawal deal on Saturday, saying it fundamentally fails to deliver Brexit.

Think tanks The Bow Group and The Bruges Group, along with the pro-Brexit pressure group Fishing for Leave, have joined the Democratic Unionist Party (DUP) in opposing the government’s new EU-approved proposed exit treaty. The Bruges Group’s chairman Barry Legg called it a “defective agreement”, while Fishing for Leave’s Aaron Brown labelled it “Brexit in Name Only”.

Chairman of The Bow Group, the UK’s oldest conservative think tank, Ben Harris-Quinney said: “We were open-minded to a new deal and would support any deal that fulfils the terms of the Brexit vote with Britain leaving the EU in full, as well as both the Single Market and Customs Union.

“This deal does not do that. Serious concerns remain over Northern Ireland and future regulatory alignment with the EU the UK would be forced to comply to. We oppose this deal and call on conservative and Brexit supporting MPs to vote against it to push for a managed no-deal settlement on October 31st.”

On Thursday morning, Prime Minister Boris Johnson and president of the European Commission Jean-Claude Juncker announced that the two sides had agreed on an exit treaty. Later that evening, the EU27 endorsed the deal, and MPs will be voting on it in the House of Commons on Saturday.

The EU’s chief Brexit negotiator Michel Barnier outlined some of the arrangements for dealing with the Irish border issue: Northern Ireland will be part of a “limited” set of EU rules related to goods, and while remaining in the UK’s customs territory, would be an entry point into the EU’s Single Market. What would be of significant objection to the DUP is that that the party has lost its veto over whether new Northern Ireland arrangements come into force.

Biggest Poll Since EU Referendum Shows Big Public Majority for Honouring Brexit Vote https://t.co/eeExQyIDPW — Breitbart London (@BreitbartLondon) October 18, 2019

While some Eurosceptics may have softened to the deal — in preference over a clean-break Brexit — the Northern Irish DUP has said it was “unable to support these proposals in parliament”, adding they “undermine the integrity of the union”.

DUP MP Sammy Wilson called on his Conservative colleagues to “take a stand for the Union and join us in rejecting this deal. Internal and burdensome trade barriers will be erected within the UK without parallel consent from both unionists and nationalists. This is not Brexit.”

Mr Harris-Quinney continued in the statement that the Bow Group believes the proposed deal “fails to achieve sovereign independence of all the United Kingdom whilst committing to send in excess of £39 billion to the EU”.

The think tank also warned that the Political Declaration — which sets out the future relationship between the UK and EU — opens up the UK to regulatory alignment with the bloc as well as military cooperation, spending commitments, and abiding by Brussels’ financial regulations “which would potentially allow the EU and our parliament to further neuter Brexit”.

“A no-deal Brexit remains the closest to honouring the Brexit vote and preventing its overturning by an unrepresentative parliament. That is the cause Brexiteer and conservative MPs should be committed to. The Bow Group, The Bruges Group, and Fishing for Leave call on them to listen to the people outside of Westminster and do so,” he concluded.