Over the weekend, an executive was finally re-established after almost two years without one in the region.

The Democratic Unionist Party (DUP), which had been holding up the process, allowed a first minister to be selected after a fresh agreement on post-Brexit bureaucracy was announced by the UK government.

Politics latest: Education secretary 'confident' on childcare promise

Mr Sunak will meet with the new first minister, Sinn Fein's Michelle O'Neill, as well as the deputy first minister, the DUP's Emma Little-Pengelly, at Stormont today.

The pair have equal responsibilities and powers, but Sinn Fein has the first minister role due to it being the single largest party in the assembly.

The Republic of Ireland's prime minister, Leo Varadkar, is also expected to be at Stormont.

Speaking to reporters during a visit to Air Ambulance Northern Ireland in Lisburn on Sunday evening, the prime minister hailed the "significant progress" made "towards a brighter future for people here" following the restoration of power-sharing.

He also faced questions about Ms O'Neill's comments that she expects a vote on Irish unity to take place in the next decade.

He replied: "Obviously, everyone is committed to the Belfast Good Friday Agreement.

"But I think everyone also agrees that now is the time to focus on delivering on the day-to-day issues that matter to people, to families, to businesses in Northern Ireland."

It is Mr Sunak's seventh time in the region since he became prime minister.

There had been hopes that the Windsor Framework agreed with the EU last year would break the impasse in Belfast.

But it has taken almost a whole year for unionists to get the assurances they need to let an administration form.

Under the Good Friday Agreement, the DUP had the power to stop an executive being formed.

With the roadblocks now removed, Ms O'Neill has now become the first nationalist first minister of Northern Ireland since 1998 when the current system was introduced.

The DUP had refused to return to power-sharing over the trade border in the Irish Sea, which put checks on goods travelling to and from Northern Ireland and elsewhere in the UK.

Read more:
Sam Coates: Sunak's deal a fudge - but it's working
Impact of years without a government in Northern Ireland
Adam Boulton: Is a united Ireland within 'touching distance'?

The establishment of a "green lane" for goods which do not require mandatory checks was announced last year in the Windsor Framework, but it required expansion last week in order to meet the DUP's demands.

This was done in agreement with the EU.

And the UK government also announced that EU law will no longer apply automatically to Northern Ireland.

The UK government has pledged £3.3bn to the new executive to help with the finances, as well as £600m for public sector pay.

Ministerial roles are shared between parties based on how many seats they won in the election.

The new executive is set to meet for the first time on Monday.

Speaking to Sunday Morning With Trevor Phillips, Ms O'Neill said she expected there to be a referendum on Irish unification within the next decade.

She said: "I believe we are in a decade of opportunity and there are so many things that are changing.

"All the old norms, the nature of this estate, the fact that a nationalist/republican was never supposed to be first minister.

"This all speaks to that change."

The UK government has said it sees "no realistic prospect of a border poll".