Last Updated May 19, 2015 1:45 PM EDT
GALWAY, Ireland --Prince Charles offered a historic handshake Tuesday to Gerry Adams, longtime leader of the Irish nationalist Sinn Fein party and reputedly an Irish Republican Army commander when the outlawed group killed the prince's great-uncle, Lord Louis Mountbatten, in 1979.
The peacemaking gesture marked the first time that Adams, Sinn Fein's leader since 1983 and a reputed former Irish Republican Army chief, had ever met a member of the British royal family.
In a rare interview with CBS Evening News anchor Scott Pelley for "60 Minutes" in April, Adams insisted that while he would never try to "dissociate myself from the IRA," he was never a member. He called the armed group a "legitimate response to what was happening" in Ireland during the 30 year war known as "The Troubles."
The two men, both 66, clasped hands in a crowded reception hall at the National University of Ireland in Galway at the start of Charles' four-day trip to the Republic of Ireland and the British territory of Northern Ireland.
Adams leaned in closely to speak into Charles' ear as both men smiled amid a flurry of camera flashes. They later had a 15-minute meeting away from the media, accompanied by Sinn Fein deputy leader Martin McGuinness and other party officials.
This is Charles' third trip to the Irish Republic since the outlawed IRA called a cease-fire in 1994. On Wednesday he plans to visit Mullaghmore, where the IRA assassinated his great-uncle Lord Louis Mountbatten in 1979.
When asked if he had apologized on behalf of his movement for Mountbatten's assassination, Adams sidestepped the question. He noted that three other people, including Mountbatten's 14-year-old grandson and a 15-year-old boy, also were killed when the IRA used a remote-controlled bomb to blow up Mountbatten's yacht in the village of Mullaghmore. Mountbatten was 79.
"One couldn't help but be regretful about the loss, particularly when there are children involved," Adams said.
Northern Ireland's four-decade conflict between Protestants and Catholics left 3,700 people dead.
"Both he and we expressed regret at what had happened from 1968 onwards," Adams said, referring to the first year of the Northern Ireland conflict, when worsening street confrontations between Protestant police and Catholic protesters inspired the deployment of British troops and the rise of the modern IRA.
Adams and McGuinness said they told the prince about the need to still investigate a string of 1970s British army killings of Catholic civilians.
"We didn't ask anybody in that room to apologize for anything," McGuinness said.
This is Charles' third trip to the Irish Republic since the IRA called a truce in 1994. The underground group made its cease-fire permanent in 2005 by disarming and renouncing violence, but IRA splinter groups remain active.
On Wednesday, Charles plans to visit Mullaghmore and attend an ecumenical service of reconciliation at the church where the poet W.B. Yeats is buried.
Charles' mother, Queen Elizabeth II, completed her only visit to the Irish Republic in 2011. At that time Sinn Fein officials refused to meet the queen, but she traveled the following year to Belfast and shook hands with McGuinness, deputy leader of Northern Ireland's power-sharing government, and invited him to Windsor Castle last year.
Adams denies ever being an IRA member. The British and Irish governments say Adams and McGuinness both were IRA commanders from the early 1970s to the mid-2000s.
For most of his career, Adams has offered an unwavering defense of IRA actions. In 1979, Adams called Mountbatten's killing a justifiable "execution" given his service as a Royal Navy commander and the last viceroy of colonial India.
"What the IRA did to him is what Mountbatten had been doing all his life to other people. With his war record, I don't think he could have objected to dying in what was clearly a war situation," Adams said at the time.