Boris Johnson has held talks with Northern Irish leaders in a bid to restore devolved power to Stormont - but the shadow of Brexit is looming large.
The Prime Minister said the region had been without its Assembly “for much, much too long”, ahead of his visit on Wednesday, and he wanted to get it back up and running as soon as possible.
Arriving at Stormont House, Mr Johnson said his "prime focus" was to get institutions back up and running, and that he expected Brexit "to come up a little bit" in Wednesday's talks.
But, in a sign of how fraught his visit would be, Sinn Fein insisted the focus will have to be on Brexit and its potential impact on island of Ireland.
Its president Mary Lou McDonald told BBC Radio 4's Today show: "I can say this without fear of contradiction that, for everybody across society, Brexit has raised fundamental questions around the wisdom and the sustainability of the partition of our island which we've lived with now since the 1920s.
"It's changed the entire political dynamic, it's changed the parameters of the conversation and it's changed minds."
Asked how impartial he could be given the Tory links to the DUP and the private dinner he attended with the party's politicians on Tuesday night, Mr Johnson insisted neither of these would affect his judgement.
"It's all there in the Good Friday Agreement," the Prime Minister said.
"We believe in complete impartiality and that's what we are going to observe.
The dinner came amid ongoing negotiations aimed at renewing the Conservatives' confidence and supply deal with the unionist party which is keeping Mr Johnson's minority Government in power.
DUP leader Arlene Foster maintained the confidence and supply deal had not been the focus of the dinner, defending the cash-injection it had brought to Northern Ireland.
The first of the Prime Minister's talks was with Sinn Fein.
Ahead of the meeting, the party's Mary McDonald branded Brexit a "piece of astonishing political and economic self-harm".
Mrs McDonald said she told Mr Johnson that provision of the agreement must be triggered in the event of a no-deal Brexit.
"The way out of this for Ireland, if he is intent on crashing, if that's the outcome, the way out for us democratically is to have a border poll and to allow Ireland and Irish people to decide our future," she said.
She accused Mr Johnson of being "complacent" about the damage she said the "Brexit nightmare" would inflict on the island of Ireland.
"His course of action, which seems to us that he has set the compass for a disorderly and a crash Brexit, we have challenged him very strongly on that policy," she said.
"We set out very clearly that this would be catastrophic for the Irish economy, for Irish livelihoods, for our society, for our politics and for our peace accord.
"We made it clear to him that the extensive planning he tells us he is carrying out in respect of a potential crash Brexit has to include the constitutional question and the issue of a border poll here in Ireland."
Speaking after her meeting with Boris Johnson, DUP leader Arlene Foster said Mr Johnson told her he would never be neutral on the Union, but would act in a neutral way in the administration of governance in Northern Ireland.
She also rejected criticism of the confidence and supply deal.
"Let me be very clear we are not going to apologise for delivering an extra £1 billion for the people of Northern Ireland," she said.
"The fact we have been able to help the health service, the education system, the fact we are putting £150 million into a broadband system which has now been procured. The fact we have helped with roads infrastructure.
"Not any other party that has stood before you today has delivered one penny of money for the people of Northern Ireland, we have delivered that through our confidence and supply agreement and we will continue to work for the people of Northern Ireland, regardless of their background.
"Don't forget this money goes directly to those people in services, through hospital care, we think that is something that should be celebrated and not denigrated in the way it has been done today."
What happened to the powersharing agreement?
The last DUP/Sinn Fein-led powersharing coalition imploded in January 2017 when the late Martin McGuinness quit as Sinn Fein deputy first minister amid a row about a botched green energy scheme.
The fallout over the Renewable Heat Incentive (RHI) was soon overtaken by disputes over the Irish language, same-sex marriage and the toxic legacy of the Troubles.
Mr Johnson said he is going to do “everything in my power” to help the parties reach agreement.
"Clearly the people in Northern Ireland have been without a government, without Stormont, for two years and six months, so my prime focus this morning is to do everything I can to help that get up and running again because I think that's profoundly in the interests of people here, of all the citizens here in Northern Ireland."
Northern Ireland Secretary Julian Smith welcomed Mr Johnson’s encouragement of the parties and met him as he arrived at Stormont House.
On Tuesday, it emerged that Mr Johnson had clashed with his Irish counterpart over the Brexit backstop in their first phone call since the Tory MP became Prime Minister.
Mr Johnson told Taoiseach Leo Varadkar that he will approach Brexit negotiations in “a spirit of friendship” but reiterated that any fresh deal must see the backstop abolished, Downing Street said.
Mr Varadkar told him the emergency measure to prevent a hard border on the island was “necessary as a consequence” of UK decisions, the Irish Government said.
Mr Johnson’s visit on Wednesday is his first to Northern Ireland as Prime Minister.
It comes following visits to Scotland, Wales and cities across England earlier this week.
He previously announced that the Mid South West Growth Deal in Northern Ireland will receive a share of £300 million new funding, to help boost business and enhance opportunities for people in the region.