Rishi Sunak has escaped an overly damaging Commons rebellion over his revised plan for post-Brexit Northern Ireland trade, winning a vote on the measure with 22 of his own MPs voting against the deal. Among the Conservative rebels were Boris Johnson and Liz Truss, another former party leader, Iain Duncan Smith, and the former cabinet ministers Jacob Rees-Mogg, Priti Patel and Simon Clarke. The vote was passed by 515 votes to 29. A breakdown of the votes showed that six Democratic Unionist party (DUP) MPs opposed the plan, with two of their colleagues acting as tellers, along with the 22 Tories, plus the former Tory MP Andrew Bridgen, who has lost the whip. Another 47 Conservatives recorded no vote. While it is not known which of these abstained and which were absent with permission, it is understood that only a few had been allowed to miss the vote, meaning dozens more Tory MPs chose to not back the plan. While this is a larger rebellion than expected earlier this week, some had forecast as many as 30 or 40 Tories could reject the measure after Johnson and Truss announced on Wednesday they would be voting against it. In a boost for No 10, the result means Sunak and his ministers did not need to rely on opposition votes for it to pass, as would have been the case if 34 or more Conservative MPs had rebelled. During a visit to RAF Valley in Anglesey, north Wales, on Wednesday evening, Sunak praised the “incredibly strong support” for his agreement. “It passed very solidly with Conservative votes and that is because it is a good deal for people, for families, for businesses in Northern Ireland,” he said. “The Windsor framework restores the balance of the Belfast Good Friday agreement, it secures Northern Ireland’s place in our union, it restores sovereignty, and for all those reasons, I’m pleased that it commanded such strong support, we’re going to implement it now and make sure we can look forward to a bright and better future for Northern Ireland.” The Conservative party chair, Greg Hands, told ITV1’s Peston programme “we’ll have to see” whether the former prime ministers Boris Johnson and Liz Truss will be punished for defying the whip in the vote. “Obviously, it was a three-line whip, we expect Conservative MPs to support that,” he said. There were concerns earlier on Wednesday that the process could descend into internal Tory party acrimony, after a minister said Johnson risked being seen as “a pound-shop Nigel Farage” for voting against the plan. Steve Baker, a Northern Ireland minister who was formerly a leading backbench Conservative Brexiter, told Sky News that Johnson had “got a choice” with his vote: “He can be remembered for great acts of statecraft that he achieved or he can risk looking like a pound-shop Nigel Farage. And I hope he chooses to be remembered as a statesman.” The European Research Group (ERG) of Brexit-supporting Tory MPs, formerly chaired by Baker, recommended its members did not support the plan, which revamps the protocol Johnson agreed, seeking to ease trade in goods between Northern Ireland and the rest of the UK. The DUP also came out against the deal. The vote was to approve only one element of the deal, the so-called Stormont brake veto on new EU regulations, but has been seen as a proxy for approval of the entire plan, formally known as the Windsor framework. The result will also bring credit to Chris Heaton-Harris, another staunch Tory Brexiter, who is now Northern Ireland secretary. Introducing the plan in the Commons at the start of a debate lasting 90 minutes, Heaton-Harris said Sunak’s plan was “a very, very good deal”, while the Stormont brake would stop Northern Ireland automatically remaining in step with changing EU regulations. “It addresses the democratic deficit, restores the balance of the Belfast Good Friday agreement and ends the prospect of dynamic alignment,” he said. “It restores practical sovereignty to the people of the United Kingdom as a whole, and to the people of Northern Ireland in particular.” Heaton-Harris received hostile interventions from some MPs, including Mark Francois, the chair of the ERG. Francois said the EU could object to new laws being halted by the brake mechanism, at which point the issue would go to arbitration: “That is a route to arbitration, isn’t it – that is not a veto?” The DUP’s Westminster leader, Jeffrey Donaldson, said his party could not agree to a deal as it stood, saying: “What I am not accepting is a situation where every business in my constituency must comply with EU rules even if they don’t sell a single widget to the European Union. That is wrong, because it harms our place in the internal market of the United Kingdom.” Earlier, Donaldson confirmed in a tweet that the DUP, which has boycotted Northern Ireland’s devolved assembly for more than a year in protest at the existing post-Brexit protocol, would not return, saying there was “not a sustainable basis at this stage to enable us to restore Stormont”. Some observers think the DUP could eventually return, but want to wait until elections to the assembly in May, so as to shore up their core vote.