President Michael D Higgins has paid tribute to peace activist Betty Williams, who has died aged 76.
Ms Williams was a Nobel Laureate and one of the founders of Peace People, along with Mairead Corrigan Maguire and Ciaran McKeown.
The organisation was founded in 1976 during the Troubles as a protest movement against the violence in Northern Ireland.
Ms Williams and Ms Corrigan Maguire were awarded the Nobel Peace Prize in 1976 for their work in trying to encourage a peaceful resolution to the violence.
Ms Williams left Peace People in 1980 and emigrated to the United States in 1983. She returned to Ireland in 2004.
President Higgins said he had learned about the death of Ms Williams with "great sadness".
In a statement, he said: "Her response to the terrible loss of life, including the deaths of the three children of Annie Maguire, inspired her to found a movement for peace.
"This was a commitment she brought with her to the end in her work on conflict resolution and children's rights.
"Working for peace became her whole life and she will be missed, not only by her relatives but by her many friends at home and abroad."
Taiseach Leo Varadkar hailed Betty Williams as a pioneering peace advocate.
"A crusader for peace and reconciliation around the world, she dedicated her life to conflict resolution, children's rights and building a better future for all," she said.
"It is hard today to fully appreciate the courage and conviction it would have taken to stand up publicly and speak out against the violence that ravaged Northern Ireland in the 1970s.
"Betty Williams never lost that fighting spirit. She will be fondly remembered for her contribution to peace."
Tánaiste Simon Coveney said Ms Williams and the Peace People organisation gave a message of hope and determination for a better future.
Very sorry to learn of passing of Betty Williams, campaigner for peace & Nobel laureate. As co-Founder of the Peace People she stood up at a time of violence, to give a message of hope & determination for a better future. Our thoughts & sympathies are with her family.— Simon Coveney (@simoncoveney) March 19, 2020
Ms Corrigan Maguire also said it was with "the greatest sadness" that she heard of the death of and co-worker for peace.
"Betty was a woman of great courage with a passion for peace and a love and compassion for all children," she said.
"Betty will be sadly missed but remembered lovingly by all of us who knew Betty. I felt privileged to know her as a great peace activist and friend."