IT remained unclear last night what form an investigation will take into the 'cash for ash' scandal.
First Minister Arlene Foster told the assembly yesterday she supported "an independent investigation, free from partisan political interference, to establish the facts around the Renewable Heat Incentive scheme".
She said it "must be conducted speedily to assist in the process of building public confidence".
"I have been working to reach agreement with officials and others on the precise details of such an investigation over the last number of days," she said.
Sinn Féin has said an investigation should be "independent, time-framed robust and transparent" and headed by a judicial figure appointed by the Attorney General.
It remains unclear whether such an investigation would look at all applications to the scheme to determine if any money could be recouped.
There is also no indication whether any probe would have the power to compel witnesses or documents or refer people who have misused the scheme to police.
Last week former DUP economy minister Jonathan Bell called for a judge-led public inquiry into the initiative which could cost taxpayers £400 million.
"I think the situation is so significant that you first of all have to deal with a major problem you can't stick a plaster over a gaping wound and you deal with it by means of a public inquiry," he said.
