Sinn Fein leader Gerry Adams said Tuesday that Northern Ireland was on an irreversible course to peace despite what he said were the fears of his chief Protestant opponent, Ian Paisley. Adams, whose Irish Republican Army-linked party represents most Catholics in Northern Ireland, was in Norway to tell a meeting of peace mediators about his own experiences in seeking an end to the province's 37-year-old conflict. "Our peace process has not yet reached its destination, but certainly has made a huge amount of progress," Adams said at a news conference. The next stage of Northern Ireland's 13-year-old peace process comes Thursday, when the prime ministers of Britain and Ireland, Tony Blair and Bertie Ahern, return to Belfast to oversee negotiations among the four parties supposed to form a Catholic-Protestant administration. Such power-sharing was the central goal of the Good Friday peace accord of 1998, but a previous coalition collapsed in October 2002 over an IRA spying scandal.