Secretary of State Chris Heaton Harris has reiterated his commitment to calling an Assembly election if power sharing is not restored.
It comes as the Secretary of State meets political parties here after being re-appointed to the position by Prime Minister Rishi Sunak. Mr Heaton-Harris has said the law requires him to call an election at one-minute past midnight on Friday morning should power sharing not be restored.
In a tweet, Mr Heaton-Harris said: "My priority is for NI's political leaders to come together and restore the Executive. The people of Northern Ireland deserve a fully-functioning devolved government so I understand the public’s frustration. However, if the parties will not re-form, I will call an election."
On Tuesday new Prime Minister Rishi Sunak reappointed the MP for Daventry to the post he was first appointed to in September by Liz Truss.
The comments come as Northern Ireland businesses say they are facing a "tipping point" and require the help of a functioning Stormont Executive.
Business leaders have stressed the need for the executive at Stormont to be restored.
The DUP is blocking the functioning of the power-sharing institutions in Belfast as part of their protest against the Northern Ireland Protocol which has created barriers on the movement of goods between Great Britain and Northern Ireland.
Mr Heaton-Harris is due to meet with DUP leader Sir Jeffrey Donaldson at 1.30pm today.
In response to Prime Minister Rishi Sunak's promise to unite the country, Sir Jeffrey Donaldson tweeted: "Uniting our country - the United Kingdom means replacing the protocol with arrangements that respect and restore Northern Ireland’s place in the Union. The integrity of the U.K. Internal Market must be properly protected."
Ahead of the meeting with Mr Heaton-Harris, Sinn Féin's Michelle O’Neill tweeted that she wants to see the Executive up and running.
She said: “Restoration of the Executive is the number one priority to help workers and families."
Gillian McAuley president of the NI Chamber, and vice president Cathal Geoghegan, said this week was "pivotal" for the Northern Ireland economy. In a joint statement: “Alarm bells are ringing, with one in five businesses telling us that they are just covering costs. "We are at a tipping point that at the very least requires a functioning Executive "While a functioning Executive will not solve all the problems, the in-tray of overdue reforms and resultant crises continues to grow." "We are on a downward trend and now is the time for action; to build confidence, protect jobs and encourage investment. "Over 170 days have passed since the election and within days we could be without local ministers. "Today, we urge all our political stakeholders at Stormont and in Westminster to reach a resolution with the sense of urgency it demands."
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