Gerry Adams has said the republican movement must face up to its own role in the Troubles.
The Sinn Féin leader said a lasting peace in the North can only be achieved when both sides acknowledge their part in causing suffering.
He was been speaking at a party election rally, in his first public appearance south of the border since his arrest last week in connection with the murder of Jean McConville.
He also told supporters that the death of Mrs McConville was "dreadful and unjust".