Minister Michael Noonan is expected to announce wide scale changes to the help-to-buy scheme today.
The plan aimed at helping first-time buyers get on the property ladder has been met with criticism since it was announced in the Budget last week.
Critics also say the scheme, which includes mortgages of up to €400,000, could encourage people to take on too much debt.
The mortgage percentage threshold and the value of property to which the scheme applies are all expected to be lowered.
However Sinn Féin's Pearse Doherty has said that the proposed alterations cannot change the fact that the scheme can only drive house prices up.
"What we need to do is actually deal with the proper end of this scale ... and that is the issue of supply," he said.
"And one of the key areas where the Government needs to step in is to actually start building their own houses in terms of social housing, which will relieve the rental market and will help in dealing with a number of problems.
"But the idea that you will actually increase demand at a time when supply is constricted is absolutely nonsensical."
