BRIAN COWEN'S struggling minority government could collapse today, after the three independents who command the key swing votes in the Dáíl refused to confirm their backing for the crucial Finance Bill.

TDs Michael Lowry, Jackie Healy-Rae and Mattie McGrath have all refused to pledge their votes in favour of the Bill, which is set to be the last piece of legislation sent through the Oireachtas before Brian Cowen goes to Áras an Úachtaráin and asks the President to dissolve the Dáil, formally calling the general election.

Cowen had planned to do that after a final ceremonial sitting of the Dáil next Tuesday - but the government may collapse this afternoon, if the three independents do not offer their support for the Bill.

With their three votes undecided, the government can expect only to win the vote on the 'second stage' by 80 votes to 79 - with Fianna Fáil needing the support of its former coalition partners in the Greens, and its former Wicklow TD Joe Behan, to retain its majority and defeat the Fine Gael-Labour-Sinn Féin opposition bloc.

The support of the independents will likely only be won if, before the vote at noon, the three independents are given assurances about the government's intentions of bringing further amendments to the Bill in the Dáil later today.

In a statement released yesterday afternoon, Lowry said he could not support the Bill in its current format, citing the absence of the promised 90% tax on bankers' bonuses as a major stumbling block.

Afterward, Jackie Healy-Rae said his position was that of Lowry's, while on today's Morning Ireland, Mattie McGrath said his support would also be contingent on the banking bonus tax - saying he had been promised the tax in exchange for his support in the Budget last month.

The Irish Times reports, however, that the introduction of the 90% tax could prove impossible to introduce before the Dáil finishes its 'committee stage' on the Bill, where amendments can be brought, at 11am tomorow.

Brian Lenihan all but confirmed the bonus's absence in the Dáil yesterday, saying there were "immense legal difficulties" with the proposal which would require further time to put together.

A further wedge was drive between Fianna Fáil and the Greens, meanwhile, after the Greens' Senator Mark Deary called on Lenihan to reverse a proposed change to the tax deadline for self-assessed earners, which is brought forward from October 31 to September 30 under the Bill.

The exact fate of the Bill will be known shortly after 12:10pm this afternoon; if the Bill is beaten, the government will be deemed to have lost the confidence of the House, requiring Brian Cowen to seek the dissolution and immediately kick off the general election campaign.

Regardless of when the general election is called, the UNITE trade union has asked members to quiz their local candidates about their opinions on emergency legislation to bring in a bankers' tax in the next Dáil.

Voting chart

If the three undecideds vote against the Bill at noon, the Finance Bill will be defeated by 82 votes to 80.

In favour (80): All Fianna Fáil TDs (72), all Green Party TDs (6), Mary Harney, Joe Behan

Opposed (82) : All Fine Gael TDs (51), all Labour Party TDs (20), all Sinn Féin TDs (5), Noel Grealish, Maureen O’Sullivan, Finian McGrath, Michael Lowry, Jackie Healy-Rae, Mattie McGrath

Total: 162

The Ceann Comhairle only votes in a tie, in which case he conventionally supports the government; there are three seats vacant in the 166-strong Dáíl.