A service of reflection on Queen Elizabeth II's life will be attended by President Michael D Higgins and Taoiseach Micheál Martin in Belfast tomorrow.
The service will be one of several events and engagements during King Charles III's visit to Northern Ireland.
As part of his programme of visits across the UK, Charles visited Scotland today and a visit to Wales is planned for later in the week.
The service of reflection, due to take place at St Anne's Cathedral in Belfast, will also be attended by Sabina Higgins and Minister for Foreign Affairs Simon Coveney.
Charles, accompanied by the queen consort, will arrive at Belfast City Airport where he will be greeted by the Lord Lieutenant of Belfast, Dame Fionnuala Mary Jay-O'Boyle, and Northern Ireland Secretary Chris Heaton-Harris.
Charles and Camilla will travel to Hillsborough Castle in Co Down for several engagements.
They will hold a private audience with Mr Heaton-Harris as well as meeting representatives of political parties in the north.
The royal couple will then receive a message of condolence from the speaker of the Stormont Assembly on behalf of the people of Northern Ireland.
After, they will attend a reception at the castle, hosted by Mr Heaton-Harris, which will be attended by some members of the public.
Charles and Camilla are planning to undertake a walkabout at Writers' Square before leaving Northern Ireland.
Hillsborough in Co Down is the home of the royal residence in Northern Ireland and has been the location for much of the ceremonial activities since the death of the queen.
The proclamation of the new king was read from Hillsborough Castle yesterday by the Norroy and Ulster King of Arms Robert Noel.
Members of the Northern Ireland Assembly were to return to Stormont today for a special sitting to pay tribute to the queen, with a book of condolence also being opened.