Taoiseach Brian Cowen has urged an end to speculation over Anglo-Irish Bank's total cost to the taxpayer until it is announced in October.
The Financial Regulator will assess the ultimate bail-out bill over the next fortnight after the European Commission accepted the Government's plan to split it.
Mr Cowen refused to be drawn on reports that costs could run to 39 billion euro.
"There has been a lot of speculation in markets and market sentiment was being affected," the Taoiseach said.
"What we need to see, quite frankly, is less speculation about numbers to allow the competent authority to come forward with their view now that they know what the strategic direction of the bank is going to be."
The Taoiseach told RTE the focus on Anglo's future would be getting the maximum return from retained assets. He declined to estimate how long that could take.
Mr Cowen said there would be a better idea of time frames after Regulator Matthew Elderfield issues his analysis next month.
Under the Government's plan for Anglo, two new banks will be created and rebranded - one as a so-called Funding Bank holding customer deposits and the second an Assets Recovery Bank tasked with managing retained loans.
Meanwhile, Mr Cowen will join party colleagues on Monday at the Ardilaun Hotel in Galway for the annual pre-Dail think-in, which will this year focus on jobs.
"What I'm focused on, what the Government is focused on and what the people of this country are focused on is how we make sure that we not only identify but build on the strengths of our own economy," he said.