Rishi Sunak has said there is “fantastic cause for optimism” after arriving in Northern Ireland to meet the leaders of a new power-sharing executive that ended two years of political deadlock. The prime minister arrived in Belfast on Sunday evening in advance of a meeting on Monday with Sinn Féin’s Michelle O’Neill, who has made history by becoming the first nationalist first minister at Stormont. During a visit to the headquarters of Air Ambulance Northern Ireland in Lisburn, Sunak said political leaders had a “special opportunity” and the focus should now be on “delivering for families and businesses”. “It is great to be back in Northern Ireland this evening, a special part of our United Kingdom,” he added. “In the last few days, we have made significant progress towards a brighter future for people here. Yesterday, the assembly sat for the first time in two years. Tomorrow, the executive will meet. “Tonight, I have been meeting with volunteers and the crew at the air ambulance. It is people and services like this, and many more, that the executive can now focus on, delivering for families and businesses across Northern Ireland. And with the new deal that we have agreed, they will have both the funding and the powers to do exactly that.” Sunak’s trip caps a whirlwind week in Northern Ireland that restored devolved government after Downing Street persuaded the Democratic Unionist party (DUP) to end a boycott that had paralysed power sharing. Sunak will seek to put his stamp on that success, but any hope of a victory lap will be peppered by demands from O’Neill and other local leaders for urgent funding from London to shore up crumbling public services and infrastructure. The prime minister is also expected to meet the taoiseach, Leo Varadkar, amid tension with the Irish government over its legal challenge to the UK’s policy on Troubles-related offences. Stormont’s assembly reconvened on Saturday and appointed an executive exactly two years after the DUP collapsed the institution in protest over post-Brexit trading arrangements that unionists said undermined Northern Ireland’s position in the UK. Downing Street clinched a deal last week that assuaged DUP concerns and led to the belated formation of a devolved government based on a May 2022 assembly election in which Sinn Féin emerged as the biggest party – a milestone for Irish nationalism. Sunak’s seventh visit to Belfast will let him showcase a political win and offer some respite from bruising battles over childcare, Rwanda deportations and Conservative party divisions. On Monday he will meet O’Neill, as well as the DUP’s deputy first minister, Emma Little-Pengelly, and other members of the executive. It will be the first test of a ministerial group drawn from Sinn Féin, the DUP, Alliance and the Ulster Unionists. The executive faces crises in healthcare, the environment and other sectors. The UK government has pledged £3.3bn to stabilise finances, including £600m to settle pay claims in a public sector bedevilled by strikes. O’Neill told the Press Association: “This place has been starved of public services funding for over a decade because of the Tories in London; we can do much better than that. “That’s a fight I think we have to fight together and I think there’s a combined effort across the executive to have a proper funding model for here so we actually can do better public services and invest in the public sector workers.” The first minister said her election showed change was unfolding across Ireland and expressed hope that there would be a referendum on Irish unity within a decade. This need not destabilise Stormont, she told Sky News. “We can do two things at once: we can have power sharing, we can make it stable, we can work together every day in terms of public services while we also pursue our equally legitimate aspirations,” she said. Under the Good Friday agreement, a secretary of state should call a referendum if a majority in Northern Ireland appears to favour unification. O’Neill said this was “a decade of opportunity” to transform the status quo. “All the old norms, the nature of this state, the fact that a nationalist republican was never supposed to be first minister.”