During the final talks on the new post-Brexit deal for Northern Ireland in Windsor on Monday, Rishi Sunak briefly halted proceedings to present Stéphanie Riso, a key member of Ursula von der Leyen’s negotiating team, with a small birthday gift. The top official, who is moving to a senior European Commission role after six years living and breathing Brexit, was said by those present to have been visibly moved that the prime minister had both known and then chosen to mark the moment. It was the sort of gesture that came to be expected by the likes of Bill Clinton or Tony Blair in their heyday and suggests a clever personal touch not often associated with Sunak during the protracted negotiations to recast the deeply problematic protocol. At the press conference shortly after, Sunak and Von der Leyen announced the breakthrough that had proved elusive to both Boris Johnson and Liz Truss. A journalist from the Daily Express stood up and asked what had changed. Von der Leyen was clear: “There was a very constructive attitude from the very beginning, to solve problems, to find solutions.” That approach began almost as soon as Sunak took over at No 10, with a meeting with the European Commission chief at the Cop summit in Sharm El Sheikh, Egypt. Such was the secrecy, that all the subsequent Brussels meetings were held away from the main European Commission headquarters, and the prying eyes of a large cadre of journalists, in the Philippe le Bon building. “Because there was comparatively little running commentary that really helped,” one source said. “Unlike the trade and cooperation agreement we didn’t have to keep going back to member states to calm them down.” The spirit in which Sunak entered the negotiations – followed up after Cop at the G20 in Bali a week later and in regular phone calls – set him apart from the more belligerent approach taken by Johnson and Truss and marked a turning point in EU-UK relations. “The EU could not shift before because it did not trust Boris Johnson,” one Brussels insider said. “Sunak does what he says. He’s technically minded and was generally interested in making things work.” Sunak quickly showed his European counterparts that he was serious about making headway, and they were impressed by his mastery of detail. But it was his efforts to persuade them that he wanted warmer relations that really precipitated a breakthrough. One close ally of the prime minister, in a subtle put-down of the strategy extolled by previous Brexit negotiator David Frost, said: “I think there has been received wisdom in recent years that you only get what you want with Brussels if you take a very adversarial approach, that it’s the only way to gain respect. But I think we have proven that a very different approach gets a different result.” Sunak also managed to charm Von der Leyen, which according to EU officials was not the easiest of tasks. “The Germans like somebody who is steadfast and serious. He told her that he would do whatever it takes to get this done. He understood that trust was lacking with Truss and [Johnson] and invested massively in it.” Senior figures in No 10 make no secret that they believe the deliberate change in approach by Sunak towards Von der Leyen in particular was a gamechanger, and showed he was a “dealmaker” who could renew the reputation of the UK as a trusted international partner. The approach was the same Sunak used when he mounted an early charm offensive towards the French president, Emmanuel Macron – a direct counter to his past rival Truss, who was famously unable to say if Macron was a “friend or foe”. The warmth between Sunak and Von der Leyen in Windsor at the joint press conference was tangible, with the European Commission president calling the prime minister “dear Rishi” and repeatedly emphasising explicitly how his change of approach had yielded the deal. But other European insiders claim that while Sunak’s personality helped produce results, it was one of several factors. They claim it was clear to them that Brexit was not working in Northern Ireland – and the time had come to take a different approach. “More important probably is that it had become more and more visible that Brexit wasn’t bringing the expected results – and not only in the veggie corner of M&S but in macroeconomic terms too,” said one. Others claim the French, Germans and Irish were very much against reopening the protocol, before shifting gradually because of Sunak’s approach, and the UK’s role on Ukraine, which showed its ability to work closely with EU nations, despite having left the bloc. “It was time to act as adults,” one said. Von der Leyen also had her own reasons for wanting to get a deal over the line. Insiders claim that she wants to run for a second term, if she gets the backing of the new German government, and finally having resolved outstanding Brexit issues would help. When she took over as EC president in December 2019, Brexit was still a major issue for the EU who were concerned about the fallout across the continent. Now, however, the majority of member states have lost interest. But Von der Leyen, they say, regards it as an issue of leadership. “She had to invest a lot of political capital for very little return internally,” one insider said. However, the lack of interest in the protocol across the EU also meant that it could be more flexible about UK “cherrypicking” – always rejected by her predecessor Jean-Claude Juncker – giving Sunak the freedom to sell the deal here as a big victory. Close reading shows that the briefing notes distributed by Brussels are notably different from the command paper published by the UK. Yet EU officials claim that the substance of the deal – including the role of the European court of justice and application of EU law – has not changed, although the emphasis has shifted. The talks intensified in the weeks running up to the deal. “These things are gradual discussions that continue into the small hours in windowless buildings, with dubious sandwiches with needless amounts of egg involved,” one British official said. “On the day the deal was done some of us went to bed at 2 or 3am. People who have been saying this deal was done two weeks ago should speak to our spouses. It’s not been sitting there finished.” Yet EU insiders insist the substance of the Windsor framework was done a fortnight ago – despite Downing Street saying talks were ongoing – although they admit some of the technical aspects were being refined right up until the last moment. In return for her flexibility, Sunak rolled out the red carpet for Von der Leyen. Despite No 10 denials, Brussels insiders insist the invitation for an audience with King Charles was not their idea. The UK also laid on official cars for Von der Leyen. “We wanted to keep her happy,” is as far as one government source is prepared to go. It looks like it was worth it.