A US congressman and renowned civil rights leader has urged political leaders in Northern Ireland and the Republic of Ireland to keep their eyes on the prize.
John Lewis, who led peaceful protests over segregation at the height of the movement in 1960s America, said they should take inspiration from his own past.
The veteran campaigner was in Dublin along with governor of Maryland Martin O’Malley and Montgomery, Alabama police chief Kevin Murphy as part of a delegation from the Faith & Politics Institute (FPI).
Last year, when a group from the institute visited the Alabama state capital Mr Murphy apologised to Mr Lewis for beatings meted out to him and other civil rights activists in 1961 on the historic Freedom Rides.
The police chief also offered him his badge as a symbol of reconciliation.
In the inaugural Frederick Douglass/Daniel O’Connell lecture at the Department of Foreign Affairs in Dublin, Mr Lewis said politicians should be guided by the liberator O’Connell and his own experience as one of the Big Six leaders of the Civil Rights Movement.
“Sometimes the reconciliation we seek may take years to see, but you must know your work is not in vain,” he said.
“We must never, ever leave that house. We all live in the same house, one house, the world house. In the final analysis, we are one people, one family, the human family.
“So my friends, keep the faith. Don’t give up, give in or give out. Don’t get lost in a sea of despair, but keep your eyes on the prize.”
Mr Lewis was arrested more than 40 times and beaten during the campaigns against segregation in southern states but remained devoted to non-violence.
After Barack Obama was elected US president in 2008, Mr Lewis was honoured with the highest civilian award in the US, the Medal of Freedom.
He was also approached by one of the men who had beaten him in Rock Hill in 1963 - former Ku Klux Klan member Elwin Wilson who apologised for his actions almost 50 years on.
The FPI five day trip is part of a congressional mission to learn more about the divisions in Ireland, north and south, and gain a greater understanding of peace and reconciliation efforts.
Mr Lewis added: “The longer I live I have come to believe that non-violence is one of those immutable principles that should never be violated. It is the natural companion of the highest values of love, peace, and compassion.”
As part of the visit Mr Lewis will walk the Peace Bridge in Derry with Nobel laureate and former SDLP leader John Hume.
“I look forward to walking across the Peace Bridge in Derry-Londonderry, a bridge that unites a city once divided,” Mr Lewis said.
“I hope that as the marchers share our stories and experiences that we can encourage continued reconciliation in both our nations - America and Ireland alike.”