Taoiseach Micheál Martin is to meet British prime minister Liz Truss on Sunday as hundreds of dignitaries from across the globe descend on London to pay their respects to Britain's Queen Elizabeth.
The talks may be casual, portrayed by No 10 as chats rather than formal bilateral sessions, but Ms Truss’ meeting with Mr Martin comes against a backdrop of political tensions over post-Brexit trading arrangements.
She had been due to meet US president Joe Biden, a milestone of her early premiership, but the talks were cancelled on Saturday, with a “full bilateral meeting” scheduled instead for Wednesday, when they are set to be in New York for the UN General Assembly.
In addition to Mr Martin, Ms Truss will meet Canadian prime minister Justin Trudeau and Polish president Andrzej Duda in Downing Street on Sunday.
The weekend’s talks with world leaders are being framed by No 10 as chats to offer condolences over the queen’s death, during which politics is likely to come up.
Mr Martin has met Ms Truss in person briefly since she became prime minister earlier this month.
They were seated next to one another during a memorial service for the queen at St Anne’s Cathedral in Belfast on Tuesday.
The meeting with Mr Martin comes as Britain is expected to push ahead with legislation to give ministers the power to scrap parts of the Northern Ireland Protocol.
Irish and EU officials believe the move to unilaterally revise the post-Brexit treaty would breach international law.
The issue is expected to ramp up ahead of a deadline at the end of October to form a new Northern Ireland Executive, which the DUP has so far blocked in protest over the protocol.
Ms Truss kicked off her meetings with world leaders on Saturday, speaking to her counterparts from New Zealand and Australia.
The talks were held at the UK government’s Chevening country residence, rather than Chequers, which is said to be undergoing routine maintenance work after Boris Johnson’s exit.
Ms Truss will also have an audience with King Charles at Buckingham Palace on Sunday, before attending his reception for visiting heads of state.
At 8pm, she will observe a minute’s silence with the country to mourn the queen’s death and reflect on her life and legacy.
