Theresa May is due to fly into Northern Ireland today amid growing speculation that a deal to restore the powersharing government is imminent.
The UK Prime Minister will meet with Stormont's main political parties as they continue talks aimed at ending the 13-month political stalemate.
A Downing Street official said Mrs May will take part in a series of meetings at Stormont House alongside Irish Taoiseach Leo Varadkar and encourage Sinn Fein and the Democratic Unionists to resolve their differences.
A spokesman for Mr Varadkar said he and Mrs May would assess the state of play in the negotiations between the parties.
In a sign that the dynamic at Stormont has shifted gears, the Taoiseach has cancelled a scheduled meeting with Welsh First Minister Carwyn Jones in Dublin on Monday in order to head to Belfast.
Downing Street added that the PM will make clear that the UK Government remains fully committed to the restoration of powersharing, devolution and the Belfast Agreement.
She is expected to tell the parties that she believes progress has been made in recent days and reiterate that the UK and Irish governments - as part of the three-strand approach set out in the Belfast Agreement - will continue to work with them to see an agreement reached.
The PM will restate her strong belief that a fully functioning Executive, empowered to take decisions over local matters, is the best way to serve the interests of the whole community, her spokesperson said.
Northern Ireland has been without a functioning government since January last year and several rounds of talks to resolve the crisis have failed.
However, speculation has been growing that a deal between Sinn Fein and the DUP is close.
Both parties publicly acknowledged on Friday that progress had been made.
On Saturday, Sinn Fein's Stormont leader Michelle O'Neill said talks are likely to draw to a close this week.
The DUP/Sinn Fein-led coalition imploded amid a row over a botched green energy scheme that widened to take in long-running disputes over culture, social issues and legacy.
SDLP leader Colum Eastwood warned that any deal to restore powersharing must end the cycle of political stand-off between Sinn Fein and the DUP.
He said it is not enough to simply form a new executive.
"The real change necessary is an end to the cycle of two parties who have proved themselves very good at the art of political stand-off, but very bad at the responsibility of government," Mr Eastwood said.
"That is the joint DUP/Sinn Fein status quo that must now end."
He added that when powersharing is restored, focus must return to the threat posed by Brexit, the economy and the health and education crises.