Power sharing will return to Northern Ireland on Saturday after two years, with Sinn Féin’s Michelle O’Neill making history as she becomes the first nationalist first minister. Here are answers to some of the key questions surrounding the historic event. What is happening at Stormont on Saturday? Members of the legislative assembly (MLAs) will return to Parliament Buildings in Belfast after a political impasse that has lasted for two years. Several previous attempts to restart the devolved government have failed since the 2022 assembly elections. This time the Democratic Unionist party (DUP) has stated it will support the restoration of the power-sharing executive, which needs the support of the largest parties in unionism and nationalism to operate. This will end the deadlock, allowing a new speaker to be elected and clearing the path for parliamentary business to resume. Michelle O’Neill, of Sinn Féin, will be nominated as first minister, while a DUP MLA will fill the role of deputy first minister. The party has not yet confirmed who it will nominate, although speculation has suggested Emma Little-Pengelly could take the position. Then a series of ministers will be appointed using the D’Hondt mechanism, which measures party strengths. Ministers will be appointed to the departments of health, education, finance, economy, communities, infrastructure and agriculture, environment and rural affairs. A justice minister will also be appointed on Saturday, although the rules are different for this department as the minister needs to have cross-community support. Sinn Féin will be entitled to three ministries, the DUP and the Alliance parties two and the Ulster Unionists one. The Social Democratic and Labour party did not win enough Stormont seats to gain a ministry and will go into opposition. What is different this time? At the 2022 assembly election, Sinn Féin emerged as the largest party in Northern Ireland for the first time. This means their Stormont leader, O’Neill, will make history as the first nationalist first minister in the region’s history. The republican party has emphasised that this is a moment of significance, with the party leader, Mary Lou McDonald, stating that their ultimate goal of Irish unity is now within “touching distance”. However, under the rules of power sharing, the offices of first and deputy first minister, filled by the largest parties from the nationalist and unionist communities, have equal authority. All decisions are taken on a joint basis. What happens after Saturday? The business of governing Northern Ireland will begin. A first meeting of the executive will take place early next week followed by the first plenary session of the new assembly. Party leaders from executive parties have already met to discuss the immediate priorities to be addressed. Ministers will have bulging in-trays. Long periods without devolved government, combined with a series of budget crises in Stormont departments, have had a damaging impact on public services. As part of the negotiations that led to Stormont’s return, the UK government offered a £3.3bn package to stabilise Northern Ireland’s finances, including £600m to settle public sector pay claims. Ministers will be expected to begin making decisions quickly to alleviate some of the pressures facing public services. Why has there not been a devolved government for two years? During the Brexit divorce talks, the then prime minister, Boris Johnson, negotiated the Northern Ireland protocol with the EU to ensure the continued free movement of goods on the island of Ireland. However, this led to the requirement for checks on goods travelling between Great Britain and Northern Ireland and was deeply unpopular with unionists, who described it as an Irish Sea border. After feeling that Westminster was not responding adequately to his concerns, the DUP leader, Sir Jeffrey Donaldson, collapsed the Stormont power-sharing institutions when he withdrew Paul Givan as first minister two years ago. In response, the new prime minister, Rishi Sunak, negotiated the Windsor framework with the EU, introducing new rules on the movement of goods and a veto for the implementation of EU law in Northern Ireland. However, Donaldson insisted this did not go far enough, leading to months of protracted negotiations that have culminated in the command paper Safeguarding the Union, published by the government this week. Why has the DUP agreed to the deal? Donaldson has insisted the new arrangements have removed the Irish Sea trading border and restored Northern Ireland’s place within the UK internal market. The deal will end routine post-Brexit checks on goods shipped from Great Britain to final destinations in Northern Ireland, as well as introduce measures aimed at providing assurances around Northern Ireland’s constitutional position within the UK. The DUP leader says this is the best deal that could be achieved for the people of Northern Ireland and it persuaded him to end the DUP boycott. He has long argued in favour of restoring devolved government, providing his concerns over post-Brexit trade and sovereignty were addressed. Does this represent a major change to the trading arrangements agreed with Brussels? It depends who you listen to. Donaldson says his party has delivered “fundamental change” to the Windsor framework by ending routine checks on goods moving from Great Britain to, and staying in, Northern Ireland. Downing Street, however, has insisted the measures unveiled on Wednesday and approved by MPs on Thursday do not require specific EU sign-off, characterising them instead as “operational” changes to the framework, without altering the “fundamentals” of the bilateral deal. Does anyone oppose the DUP leader’s move? Not everyone in the DUP supports accepting the arrangements. A meeting of the party’s ruling executive, where Donaldson presented the proposals to members, lasted for more than five hours on Monday night. He was ultimately able to secure the backing of the executive, insisting the margin of support was “decisive”, and the endorsement of the majority of his 12 party officers. However, just hours after the command paper was published on Wednesday, the senior DUP MP Sammy Wilson launched a scathing broadside against the government in the House of Commons, in a clear sign of the differing opinions at the highest levels of the party. The arch-Brexiter claimed the ongoing application of EU law in Northern Ireland was the result of a “spineless, weak-kneed, Brexit-betraying government, refusing to take on the EU and its interference in Northern Ireland”. On top of internal tensions, Donaldson faces criticism from some in the wider unionist and loyalist community. On Thursday night, the leader of the Traditional Unionist Voice party, Jim Allister, and a loyalist activist addressed a meeting of unionists and loyalists opposed to the deal. They have insisted the Irish Sea trading border has not been removed. On Friday, Allister a legal opinion commissioned by himself and others from Northern Ireland’s former attorney general John Larkin. Key among the questions asked of Larkin were whether the plans set out in the command paper would: restore the 1800 Acts of Union; remove a customs and regulatory border in the Irish Sea; and ensure “zero checks and zero paperwork” for goods from Great Britain destined for Northern Ireland. Larkin argued they achieved none of those objectives. However, Donaldson has rejected the findings of the legal opinion, stating that he “fundamentally disagreed” with it.