He left Parliament Buildings to travel the short distance to Stormont Castle, home to the Northern Ireland Executive, joined by Northern Ireland Secretary Chris Heaton-Harris.
And an extra seat was added to the Northern Ireland Executive table as Prime Minister Rishi Sunak joined ministers during his Stormont visit.
He sat between the new Deputy First Minister Emma Little-Pengelly (left) and First Minister Michelle O'Neill.
Earlier Mr Sunak was accompanied by the Speaker of the newly-restored Assembly Edwin Poots and Northern Ireland Secretary Chris Heaton-Harris.
Mr Poots told the BBC that he always enjoys the "cut and thrust" of being on the floor so his new job will be a move away to impartially refereeing.
"I will do everything I can to ensure Northern Ireland moves forward and we will keep real scrutiny on the ministers," he says.
And Taoiseach Leo Varadkar has also arrived at Parliament Buildings in Belfast where he was greeted by new Speaker Edwin Poots.
Mr Varadkar told waiting reporters it is a “very positive day” as he walked in to the building.
1.
Prime Minister Rishi Sunak (right) meets First Minister Michelle O'Neill (second left) and Deputy First Minister Emma Little-Pengelly as Northern Ireland Secretary Chris Heaton-Harris looks on at Stormont Castle, Belfast, following the restoration of the powersharing executive. Photo: Oliver McVeigh
2.
Rt Hon Chris Heaton-Harris, Secretary of State for Northern Ireland, First Minister Michelle O'Neill, Deputy First Minister Emma Little-Pengelly and Rishi Sunak, Prime Minister at Stormont Castle. Photo: presseyre
4.
Andrew Muir, Department of Agriculture, Environment and Rural Affairs arrives at Stormont Castle. Photo: presseye