Fianna Fáil and the Green Party are due to begin talks today on the renegotiation of the Programme for Government they agreed two-and-a-half years ago.
The Greens demanded the renegotiation earlier this year in light of the massive deterioration in the public finances.
They say they want to change the direction of Government policy to ensure more effectiveness in the spending of taxpayers' money.
However, they are also expected to push for the implementation of more green policies as the price for keeping Fianna Fáil in power despite its unpopularity with the public.
The new Programme for Government is due to be put before Green Party members at a special convention next week, with a two-thirds majority needed to approve the document.
Party leader John Gormley has already said the Greens will have to withdraw from the Government if members do not support the renegotiated deal.