EU: The Taoiseach has told the European Parliament he will seek to conclude negotiations on the EU's constitutional treaty in April or May if he believes a deal is possible.
Mr Ahern said an early deal would be best for Europe but he warned that EU governments must be prepared to move from their negotiating positions if agreement is to be possible.
"I passionately believe that making progress in the shorter term is the best course. But the facts are very simple. If everybody sticks to their present position, there is no hope I can do it," he said.
During a three-hour debate on the Irish Presidency in which more than 40 MEPs spoke, almost all speakers called on the Taoiseach to try to complete the constitutional talks before June.
A number of speakers expressed their relief that the stewardship of the EU had passed into a safer pair of hands after six turbulent months under Italy's prime minister, Mr Silvio Berlusconi.
The Commission President, Mr Romano Prodi, welcomed the Taoiseach's approach to reviving the treaty negotiations, but he repeated his warning that a second failure to agree could open the way to a two-speed Europe.
"Clearly, there are risks involved in any solution and the Commission is determined that we should all move forward together towards greater integration for all. If efforts in this direction were to become bogged down, it would clearly be impossible to stand in the way of a smaller number of states seeking greater co-operation that would then serve as a starting point for a more vigorous and cohesive Union, using the method that has ensured the success of 50 years of European integration," he said.
A number of MEPs called for an end to talk of a two-speed Europe, but Fine Gael's Mr John Cushnahan, said governments should heed Mr Prodi's warning.
"If unanimous agreement on the constitutional treaty cannot be achieved, then the only alternative is the creation of a two-speed Europe. To do otherwise would be to give the power of veto to any eurosceptic member-state.
"A two-speed Europe already exists in at least two areas namely, the Schengen Agreement and the single currency Given these experiences, we should not be alarmed at the prospect of taking similar decisions in other areas rather than face paralysis and stagnation at the hands of eurosceptic member-states," he said.
The leader of the conservative European People's Party (EPP), Mr Hans-Gert Poettering, urged France and Germany to compromise on their demand for a "double majority" to replace the present system of weighted votes in the Council of Ministers.
While the leader of the Liberal Democrats, Mr Graham Watson, welcomed the start of the Irish Presidency, adding that it was appropriate that a country which speaks for the transformative power of the EU should oversee the enlargement process.
"We should not be tempted to believe that we can separate enlargement from agreement on the instrument designed to make that step possible. Integrating the new member-states into the Lisbon process and Schengen cannot hide the fact that without the additional framework of a new constitutional settlement we are simply changing the oil in a union which needs a new engine," he said.
A number of MEPs offered suggestions as to the criteria EU leaders should use to choose the next Commission President, with some demanding that the largest group in the European Parliament should nominate Mr Prodi's successor while others insisted that any candidate should have broad support among MEPs.