Green Party leader John Gormley has rejected suggestions that National Asset Management Agency projections, which were introduced in the Dáil, were the work of Fianna Fáil ministers only.
Mr Gormley said the information had been prepared and assembled independently on behalf of the Government and the taxpayer would be protected at all times by the legislation.
Addressing members of the Heritage Council, the Minister said there would be no further 'bubble development' allowed.
He said that he was proposing an 80% windfall tax on all building sites disposed of under the NAMA legislation.
Meanwhile, a number of significant investors are expected to make an announcement in the coming days that they will be prepared to buy property loan portfolios from Irish banks.
It is understood the institutions concerned are already investors in the banks.
It is believed the plans will involve investments of billions of euro if they proceed.
The development will mean that NAMA will not be the only purchaser of distressed loans from the banks.
Minister for Finance Brian Lenihan said he would welcome entrants into the banking market last night.