The Taoiseach has called on nationalists and republicans to apply to join the new Police Service of Northern Ireland "in great numbers" once the Patten recommendations have been implemented.
Welcoming the British government's announcement on policing in Northern Ireland, Mr Ahern said he looked forward to a detailed implementation plan.
Asked in Ballaghaderreen, where the Cabinet met yesterday, if he believed nationalists and republicans should now consider joining the police service, he said: "We are at that stage."
Subject to the passage of legislation to implement the Patten recommendations, "we are reaching a time where people can have confidence in the reformed force".
When recruitment starts, he said, "I hope that nationalists are in great numbers putting their names forward".
He pointed to the Belfast Agreement's statement that there was now a unique opportunity for "a new beginning to policing in Northern Ireland". The "effective implementation" of Patten "should open the way for young nationalists and republicans to join with their unionist contemporaries as partners in the new police service.
"I urge everyone concerned to recognise the huge opportunity for positive change in policing which now presents itself and to respond accordingly."
He said the Patten report offered a blueprint for a representative and effective police force. It was highly significant and encouraging that the British government had accepted the great majority of the Patten proposals. It was vital that an oversight commissioner be appointed as quickly as possible.
He said people from both traditions wanted to be able to give their unqualified support to a police service "which is unequivocally of and for the community as a whole.
"They want the law to be upheld in an atmosphere of normality and security and police men and women to be made welcome in every house. A career in policing should be fully open to talented and committed people irrespective of their political beliefs and identities," he said.
The Government would ensure the further development of North-South policing so-operation, in the interests of maintaining security and combating crime throughout the island.
He acknowledged that some people would find it hard to accept some of the changes announced yesterday, while others would feel they did not go far enough.
"Both perspectives are understandable and come from the legacy of past pain and suffering," he said. RUC widows and disabled officers had particular and special needs which should be addressed.