Mr Sunak hailed what he said was a “major breakthrough” that marked the “beginning of a new chapter in our relationship” with the EU.
The Windsor framework will deliver “smooth-flowing trade within the whole United Kingdom, protects Northern Ireland’s place in our union and safeguards sovereignty for the people of Northern Ireland,” he said.
But in a nod to a potential clash with NI’s largest unionist party the DUP he said he recognised that they would want to “take time” to study the detail.
The pound jumped as markets welcomed the move amid hopes it will ease EU/UK tensions in the wake of Brexit.
At a press conference in Windsor the prime minister said the deal was a “turning point” for the people of NI because his deal would remove “any sense of a border in the Irish Sea”.
After striking the deal Ms von der Leyen had tea with the King at Windsor Castle despite criticisms the meeting would drag Charles into the politically contentious issue.
The deal on the Northern Ireland Protocol is designed to solve problems in post-Brexit trading arrangements with the EU.
In a bid to avoid a hard border in Ireland after Brexit, NI remains in the EU’s single market for goods.
But unionists argue that simply replaces one unacceptable border with another - this time down the Irish Sea, separating NI from the rest of the UK.The new arrangements are expected to ease those tensions including by reducing checks on good travelling into Northern Ireland from GB.
Mr Sunak will now hope his new deal wins the backing of the DUP, Northern Ireland’s largest unionist party, and convinces them to re-enter power-sharing in the government there, which is currently in abeyance.
The prime minister received a massive boost earlier when Northern Ireland minister and hardline Brexiteer Steve Baker emerged smiling from No 10 and told reporters: “I can only say this, the prime minister is on the cusp of securing a really fantastic result for everyone involved.”
His wholehearted support appeared to make a nonsense of claims that he was on the verge of resigning over compromise which maintained a role for the European Court of Justice (ECJ) in Northern Ireland.
Tory Brexiteer Jacob Rees-Mogg put Mr Sunak on notice of a possible Tory revolt, however – claiming that the support of both former prime minister Boris Johnson and the DUP were vital in getting it through parliament.
But former cabinet minister David Davis and several senior Brexit-backers have told The Independent they expected a rebellion to be limited to only 20 to 30 Tory MPs.
Writing for The Independent, Mr Davis described the deal as a “formidable achievement”, saying he was satisfied there would be a “major reduction” in the power of European judges and a “democratic check” on new EU rules that apply to Northern Ireland.
The DUP dismissed a report in the Irish News newspaper that the party would back the deal. The newspaper, citing a source with knowledge of the party’s thinking, said a London dinner was “pencilled in” with supporters tonight to explain the rationale for supporting Mr Sunak.
However, DUP leader Jeffrey Donaldson ridiculed the report, tweeting: “Anonymous sources strike again. We’ll take our time to consider the detail and measure a deal against our seven tests. PS – A busy day and no dinner planned either – story entirely fictional.”
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