The Taoiseach and the British Prime Minister have arrived at Stormont amid growing speculation that a deal to restore the power-sharing government is imminent.
Varadkar and May at Stormont for power-sharing talks
Leo Varadkar and Theresa May will meet Stormont's main political parties as they continue talks aimed at ending the 13-month political stalemate - writes rte.ie.
A spokesman for Mr Varadkar said he and Mrs May would "assess the state of play in the negotiations between the parties".
"The Taoiseach will use his visit to encourage the parties to reach an agreement so that functioning institutions can commence work again in the interests of the people of Northern Ireland," he said.
A Downing Street spokesman said Mrs May would take part in a series of meetings at Stormont House and encourage Sinn Féin and the DUP to resolve their differences.
In a sign that the dynamic at Stormont has shifted gears, the Taoiseach cancelled a scheduled meeting with Welsh First Minister Carwyn Jones in Dublin in order to head to Belfast.
Northern Ireland has been without a functioning government since January 2017 and several rounds of talks to resolve the crisis have failed.
However, speculation has been growing that a deal between Sinn Féin and the DUP is close. Both parties publicly acknowledged on Friday that progress had been made.
On Saturday, Sinn Féin's Stormont leader Michelle O'Neill said talks were likely to draw to a close this week.
The DUP/Sinn Féin-led coalition imploded last January amid a row over a botched green energy scheme.
That rift subsequently widened to take in long-running disputes over culture, social issues and legacy.
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