RHI scandal: Sinn Fein digs in over probe demands and DUP leader stepping aside
Sinn Fein has vowed it will not move on from the cash for cash scandal unless there is an independent investigation and Arlene Foster steps aside.
Health Minister Michelle O'Neill said any probe should have the power to compel witnesses and papers and be free from ministerial influence.
Taking the reins of her party for the second time this week in the absence of Deputy First Minister Martin McGuinness, Mrs O'Neill added: "We need a judicial figure who will lead an investigation to cover all the issues - who did what, when and how - a judicial figure, independent of any minister or any of the Executive, who will take forward an investigation.
"At the heart of that has to be compellability, because if they can't compel people and papers, then the investigation is not going to work."
Mrs O'Neill also told reporters there was no agreement between Sinn Fein and the DUP on two of the party's key demands for an investigation - the First Minister stepping aside and the issue of compellability.
"There's certainly no agreement at this moment in time," the Health Minister explained.
"For us, this is an issue of public confidence, and we have to deal with that. If Arlene Foster wants to do the right thing, the right thing would be to step aside. We've clearly said compellability has to be at the heart of this, and the DUP has a decision to make in relation to that.
"If they're serious about addressing the issue of public confidence, they really should step up and be endorsing the fact we need compellability."
Asked if Sinn Fein would agree to an investigation going ahead with Mrs Foster still in her position, Mrs O'Neill replied, "No".
Mrs Foster gave a similarly abrupt response yesterday afternoon when asked if she would accept the Sinn Fein proposals.
Under rules outlined in the Good Friday Agreement, both parties of the Executive must agree on how the RHI crisis is investigated.
Sinn Fein has already rejected proposals drawn up by the head of the Civil Service over claims they fell short on a number of issues, chiefly compellability.
The party previously described suggestions there was agreement on the nature of the proposed process as "nonsense".
Sinn Fein wants the Attorney General to appoint a judge to head up an investigation panel, which would need emergency legislation to establish the power to compel witnesses and documents.
The party said the establishment of the panel and the emergency legislation, to be introduced under accelerated passage, should proceed simultaneously.
It would expect the findings of a preliminary report within four weeks, with the panel to produce its final report within three months.