EU leaders meeting in Brussels have so far failed to make progress on agreeing a historic new constitution for an enlarged Union of 25 countries.

There are still fears that deep divisions over voting rights and other issues could force a postponement of the new Treaty, which is aimed at simplifying and streamlining EU decision making when 10 new members join next May.

The first day of the three-day summit was dominated by bilateral meetings, some posturing and the occasional glimpse of optimism.

It was also characterised by the sight of Polish Prime Minister Leszek Miller arriving from his hospital bed after last week's helicopter crash. He spent most of the talks in a wheelchair.

Poland and Spain remain at the centre of a row over voting rights.

There are other important areas where agreement has to be reached, including how many commissioners there should be, what kind of EU foreign minister post might be created, and how to set up a more permanent EU presidency, instead of the current rotating system.

Silvio Berlusconi, as Italian president, has been listening to his counterparts, but a fresh text to be negotiated will probably not be on the table until tomorrow morning.

But there is still considerable gloom that a deal will not be reached, and that more discussions will spill over into the Irish presidency.

Ahern hopeful of accord

The Taoiseach Bertie Ahern has told RTÉ news he is hopeful agreement can be reached.

Ireland is neutral on the voting rights issue, but wants to retain the national veto on taxation and the Government has reservations on criminal justice issues.

But Mr Ahern says progress has been made on these and the Government appears confident that any mutual defence clause will not conflict with Ireland's constitutional position on neutrality.

Failure to reach overall agreement in Brussels this weekend will pitch the whole problem into the Irish presidency which begins on 1 January.