Rishi Sunak is to replace Liz Truss as prime minister after rival Penny Mordaunt conceded in the leadership contest.
Mr Sunak, a former chancellor, secured the keys to No 10 just seven weeks after he lost out to Ms Truss in a previous Tory leadership race.
One of the pressing issues facing Mr Sunak will be the political crisis in Northern Ireland where there has been no functioning Assembly for months due to the DUP protest against the workings of the post-Brexit protocol, which has created economic barriers on trade between Great Britain and Northern Ireland.
The UK Government has vowed to secure changes to the protocol, either through a negotiated compromise with the EU or domestic legislation to empower ministers to scrap the arrangements without the approval of Brussels.
If the Stormont institutions are not restored by Friday, Northern Ireland Secretary Chris Heaton-Harris has pledged that he will call fresh Assembly elections.
But what does Rishi Sunak as prime minister mean for Northern Ireland?
And what happens now for the Secretary of State Chris Heaton-Harris?
Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To Know.