Irish premier Micheal Martin will lay a wreath at the memorial to the victims of Bloody Sunday as part of a service this weekend, organisers have said.
Mr Martin will lay a wreath at the memorial to the victims of the tragedy in Londonderry, 50 years after the events of January 1972.
Mr Martin is also expected to meet privately with the families of those killed.
Thirteen civil rights protesters were shot dead by British soldiers on January 30 1972.
Another man shot by paratroopers on the day died four months later.
Organisers confirmed on Wednesday evening that the wreath-laying ceremony will take place in the Northern Irish city at around 11am on Sunday.
It will follow a walk of remembrance that will retrace the route of the original civil rights march through the city.
A specially recorded message from Irish President Micheal D Higgins will also be shown in Guildhall Square on Sunday.
Earlier, SDLP leader Colum Eastwood (Foyle) told the House of Commons the Parachute Regiment is “yet to apologise and condemn the actions of their soldiers” in the city in 1972.
But Conservative former defence minister Johnny Mercer criticised Mr Eastwood for suggesting troops were sent with the “express purposes of murdering the people who lived in Derry”.
The disagreement came either side of Prime Minister Boris Johnson telling the Commons that Northern Ireland must reconcile and build a “shared peaceful and prosperous future” as the anniversary approaches.
A Ministry of Defence spokesman said in a statement: “In 2010, the Chief of General Staff (Gen Sir David Richards) fully supported the Prime Minister’s apology on behalf of the government of the United Kingdom, the Army and those involved and this remains the Army’s position.”
At Prime Minister’s Questions, Mr Johnson echoed the words of Northern Ireland Secretary Brandon Lewis when he said: “This Sunday marks a tragic day in our history, this was one of the darkest days of the Troubles, and it’s the 50th anniversary of Bloody Sunday.
“I echo his call to learn from the past, to reconcile and build a shared peaceful and prosperous future.”