Sinn Fein leader Gerry Adams will travel to South Africa this week to pay tribute to anti-apartheid icon Nelson Mandela, he announced on Monday.
The Irish republican said he was invited to Tuesday's huge memorial service in Soweto along with dozens of world leaders including US President Barack Obama, but will be unable to attend due to prior engagements in Ireland.
Instead Adams, whose party was the former political wing of the Irish Republican Army (IRA), will attend a memorial service on Saturday in Pretoria, where the ruling African National Congress (ANC) will bid farewell to their former leader.
Sinn Fein's Martin McGuinness, the former IRA commander who is now Northern Ireland's deputy first minister, will attend Tuesday's memorial in a Soweto football stadium.
Adams said Sinn Fein was "very proud" of the republican party's "decades-old relationship" with the ANC.
Sinn Fein and the ANC have been compared as left-wing, anti-colonial movements with close links to paramilitary organisations -- in the ANC's case, its armed wing Umkhonto we Sizwe, which Mandela helped to found.
Opposed to British rule in Northern Ireland, the IRA carried out a campaign of violence during the three decades of sectarian bombings and shootings known as the Troubles.
The violence largely ended with peace accords in 1998 that paved the way to power sharing in Northern Ireland between largely Catholic republicans and mostly Protestant unionists favouring continued British rule.
Adams, now a member of the Irish parliament, has repeatedly denied that he was ever an IRA member.
The paramilitary group announced in 2005 that it was formally ending its armed campaign.
Sinn Fein continues to reject British rule in Northern Ireland.