"We are not going to go into this blind. We'll be ready for negotiations on the morning after the results are known, " a senior Sinn Fein official said.

The Sinn Fein move contrasts sharply with Fianna Fail's continued insistence that it will not do a post-election deal with the party. Gerry Adams and his colleagues believe the option will be activated in the event of a hung Dail in which Labour continues to resist entering a Bertie Ahern-led government.

Two new opinion polls published today show a slight increase in Fianna Fail support but the party is entering into the final few days of canvassing well below support levels that would prevent significant seat losses.

In a Red C poll for the Sunday Business Post, Fianna Fail is at 36%, up one point since last week, whereas Fine Gael is at 27% (down two) and Labour at 11%, down one. In the other poll, carried out by IMS Millward Brown for the Sunday Independent, Fianna Fail is up two percentage points to 37% with Fine Gael at 25% (down one) and Labour at 12%, also down one.

The poll results confirm that Fianna Fail is unlikely to be able to form a government with the PDs, but shows that Enda Kenny's alternative alliance may fall short of winning an outright Dail majority.

With the PDs ruled out as a coalition option, Fianna Fail has a difficulty in that its second preference partner, Labour, continues to reject overtures. There is a fear in Fianna Fail that this confusion over coalition options may cost the party votes in Thursday's poll, especially with Fine Gael and Labour presenting a united front to the electorate.

Sinn Fein sources said the party will seek the Department of Education in any coalition deal. This is designed to further its allIreland agenda with Caitriona Ruane already minister for education in the Northern executive. The party has already significantly moderated its stance on income and corporation taxation to become more attractive to Fianna Fail, although it will demand greater public spending as well as a commitment to publish a Green Paper on Irish unity.

In another sign of the closeness of the contest, last night PD leader Michael McDowell criticised recent Fianna Fail overtures to Labour.

"That has been Bertie Ahern's consistent position but I'm afraid that particular option has disappeared off the horizon. There is only one alternative to the Rainbow coalition and that's the PDs and Fianna Fail. And anybody who is thinking of any other arrangement is codding themselves. There will not be a Labour/Fianna Fail coalition for the very simple reason that it would be politically suicidal for Labour to do it and Fianna Fail still don't seem to understand that."

As the main parties continued to argue over policy differences in health spending and tax proposals, Pat Rabbitte described the current government as "clapped out".

Fianna Fail continued to attack Fine Gael. "In the final days of this campaign it is substance not soundbites that the public want to hear and Fine Gael should stop running and start answering, " children's minister Brian Lenihan said.

Enda Kenny will later today address a rally of party members in Temple Bar in Dublin at which he will identify his priorities for the first 100 days should a Fine Gaelled government be elected.