The Northern Ireland Policing Bill, currently before the House of Lords, is not acceptable and changes must be made, the Taoiseach, Mr Ahern, said yesterday.
However, if people "stretched themselves" and made one last heroic effort, the remaining problems could be sorted out, he said. He was addressing the British-Irish Parliamentary Body in advance of a meeting with the British Prime Minister, Mr Blair, in London today to discuss the issue.
Mr Ahern said issues which were "symbolic, substantive and of timing" had to be addressed. He was responding to the Labour MP, Mr Kevin McNamara, who asked if the Government was in a position, as the Policing Bill now stood, to recommend to nationalists that they join the force.
"The answer to that is `No' unless the changes that I mentioned are completed," said Mr Ahern. "There is no possibility Sinn Fein and the SDLP will sign up for the Bill. Then anything I would say or do would be pointless."
He said there were up to six areas which needed to be resolved.
It is understood that Mr Ahern will stand firm in this afternoon's meeting on the name of the police force, but that there is room for some manoeuvring on emblems and the composition of boards. In his speech, he said there were differences and challenges but that these were "far from insurmountable."
In the beginning, Mr Ahern said, there had been 75 differences, but just five or six were left. He described the issue of symbols as "enormous". The timing, he said, should be resolved quickly and without any great difficulty.
"But the symbolic - the name, flags and emblems - and substantive ones need to be sorted over the next few weeks."
Responding to a question from the Sinn Fein TD, Mr Caoimhghin O Caolain, about whether the Government was actively pursuing the full implementation of the Patten recommendations, the Taoiseach said he would be "shocked if people did not have a clear view of where I stood." He urged everybody involved to "stretch themselves."
He addded: "I can stretch myself until I crack. I need everybody to stretch themselves . . . There are issues that if we stretch ourselves we can conclude."
Mr Ahern said he knew things had been difficult for the Ulster Unionist Party leader, Mr Trimble. "We are committed to doing all we can. I do not share the view at all that David Trimble should move either voluntarily or otherwise."
He added: "Even if he wanted to go I would convince him not to."
He wanted to allay the concerns of unionists, he said, whose confidence in the benefits to them of the Good Friday agreement had been shaken.
"The agreement is fully transparent, and thus is not, and cannot be used as, a Trojan horse. There is no will, no desire, no possibility of anyone forcing a majority of the people of Northern Ireland into a united Ireland against their will."
However, he said, hard questions needed to be asked of those who sought to present the agreement and its implementation as a betrayal. He asked if they had any alternatives which came remotely nearer to meeting the needs of the situation.
"How can they expect to secure long-term political stability, and convince Northern nationalists and republicans to accept the constitutional position of Northern Ireland within the framework of the Good Friday agreement, if they do not attempt ever to address their concerns and if they fail to make them partners in a new political dispensation?"
He said the fears and concerns of everyone in Northern Ireland must be addressed, but the agreement was an honourable accommodation and those fears could be addressed within its context.