British Prime Minister Rishi Sunak has struck a new deal with the EU on post-Brexit trade rules for Northern Ireland and he said it would pave the way for a new chapter in London’s relationship with the bloc.

Standing alongside European Commission president Ursula von der Leyen at a news conference in Windsor, Sunak said the two sides had agreed to ease trade rules for the British province and give its lawmakers more control over the laws they have to follow.

“I’m pleased to report that we have now made a decisive breakthrough,” Sunak said, adding that they had agreed to change the original deal for Northern Ireland, known as the protocol, to create the “New Windsor Framework”. “This is the beginning of a new chapter in our relationship.”

The issue has been one of the most contentious regarding Britain’s departure from the EU in 2020. Northern Ireland had an open border with Ireland, an EU member.

Any return to a hard border could have jeopardised the 1998 peace deal which mostly ended three decades of sectarian and political violence in Northern Ireland.

For Sunak, the agreement marks a high-risk strategy just four months after he took office.