Taoiseach Bertie Ahern today wished Dún Laoghaire TD Eamon Gilmore well on his appointment as new leader of the Labour Party.
Mr Gilmore, the only candidate to put himself forward for the post to succeed Pat Rabbitte, was declared elected today.
"Deputy Gilmore has proven to be very effective public representative and has made a significant contribution to the work of Dáil Éireann," Mr Ahern said.
"Today is a very significant day in his long political career. His appointment as leader is a great honour for him and for his family and supporters."
Green Party leader and Minister for the Environment John Gormley also wished Mr Gilmore well in the challenges he faces in his new post.
He said Mr Gilmore had made a strong contribution to the work of Dáil Eireann since his election in 1989 and that he had had a distinguished career as a student leader and trade union official.
Progressive Democrats leader and Minister for Health Mary Harney said Mr Gilmore's uncontested election as leader was indicative of the strong confidence his colleagues place in his abilities.
"I have no doubt that his integrity, commitment, ability and energy will stand to him in his new role," she said.
Fine Gael leader Enda Kenny congratulated Mr Gilmore on his appointment and said his "commitment, integrity and energy" would serve him well in his new role.
Sinn Féin Dáil leader Caoimhghín Ó Caoláin said the new Labour leader was "an able politician" and encouraged him and his Labour colleagues "to engage in dialogue on the future of the left in Irish politics".
"There is a real challenge to all progressive people to end the total dominance of the two major conservative parties - Fianna Fáil and Fine Gael," he said.
Amicus trade union also said it would offer Mr Gilmore its full support in working with him in the future.
Additional reporting: PA