Taoiseach's reaction:The Taoiseach Bertie Ahern tonight paid tribute to Mary Harney saying she had demonstrated her integrity and commitment to public service in Ireland over the past few decades.
Mr Ahern, who worked with Ms Harney for nine years in her role as Tanaiste, said he saluted her for her contribution in effecting fundamental changes in Ireland.
"We entered the Oireachtas together at a time when Ireland faced enormous obstacles and in the time since our country has made enormous progress. She has made a real contribution to all that has been achieved," Mr Ahern said.
"As leaders of separate parties we haven't always agreed on policies, but we have worked together to achieve real results. She has always been an honest, straightforward and hard working leader and Ireland has benefited from her services."
Mr Ahern said the Coalition Government would continue to implement its programme for government.
"I understand Mary's decision to step down as leader of Progressive Democrats. On a personal level I want to thank her for her friendship, and wish her and Brian (Ms Harney's husband) every happiness in the years ahead and I look forward to continuing to work with Mary in public life," he said.