Prime Minister Theresa May and Taoiseach Leo Varadkar are in Belfast amid growing speculation of a power-sharing deal later this week.
The 13-month political stalemate between the DUP and Sinn Féin has a number of key issues at its heart – including the Irish language, dealing with the past, and same-sex marriage.
Sinn Féin demands for an Irish Language Act have proved to be a particular sticking point, leading to speculation three pieces of legislation - an Irish Language Act, an Ulster Scots Act and a broader Culture Act - could be developed as a means to satisfy both sides.
The two main parties have acknowledged that progress has been made.
However, a DUP source has played down expectations of a deal being finalised on Monday.
If an agreement is struck, Downing Street has said the Government is ready to introduce legislation to enable the re-establishment of a devolved executive as soon as possible.
Before heading to Stormont, the Prime Minister also paid a visit to Bombardier to meet workers at the east Belfast factory in the wake of the company’s trade battle victory with Boeing in the US.
Mrs May was given a tour of the plant, where the wings of the Canadian manufacturer’s C Series jet are built.