Sinn Féin and DUP square up over the next moves in 'cash-for-ash' inquiry
Sinn Féin has increased pressure on First Minister Arlene Foster in the controversy over the £400m (€478m) "ash-for-cash" scheme.
The stand-off between the two governing parties in Belfast again threatens the fragile power-sharing institutions. The Democratic Unionist Party rejected calls from Sinn Féin that Ms Foster stand aside as First Minister until the matter is independently investigated.
In ill-tempered exchanges, Ms Foster refused to stand aside and said she would not be dictated to by Sinn Féin.
The DUP also attempted to rally behind its leader after a dissident former minister, Jonathan Bell, had broken ranks to make serious charges against the leader and party advisers.
Mr Bell has now been suspended from the party pending an investigation. Key DUP figures, including Jeffrey Donaldson, have been mobilised to defend Ms Foster.
Sinn Féin will today bring a proposal to Northern Ireland's Assembly formally calling on Ms Foster to comply with the call first made by Deputy First Minister Martin McGuinness.
The DUP leader has been under mounting pressure over her handling of a botched green energy scheme which critics predict will cost the North's taxpayers £400m.
The DUP yesterday said it supported an independent investigation. Ms Foster is also due to outline her version of the scheme, which was part of her responsibility as a minister before she was elected First Minister last summer.
But there are likely to be continuing differences about what constitutes a robust and independent inquiry.
Mr McGuinness stepped up the pressure and signalled that Ms Foster's statements today must be treated as DUP statements rather than coming from the head of government.
"It is my firm belief the only way to establish the truth of what has occurred and to begin to restore public faith in the institutions is for an independent, time-framed and robust investigation to take place.
"The First Minister should stand aside to allow this. There is also an urgent need to minimise the cost of the scheme to the public purse," Mr McGuinness said.
"Given the First Minister's failure thus far to accept this, Sinn Féin will bring forward a proposal to the Assembly which calls on the First Minister to stand aside until this independent investigation brings forward a preliminary report."
This Sinn Féin-DUP estrangement could undermine the power-sharing institutions, which require cross-community co-operation between the two largest parties of unionism and nationalism.
The row arises from a generous scheme designed to encourage businesses to switch from burning fossil fuels. It is now predicted to cost the taxpayer millions in funds which could have been used elsewhere after inadequate cost control.
Ms Foster has denied any wrongdoing in establishing the Renewable Heat Incentive (RHI) and during the period before it was shut down. Her role is now under intense scrutiny, but she has denied any wrongdoing.
Sinn Féin leader Mr McGuinness said there is no credibility in an inquiry established solely by the DUP or in the selective release of some documents by DUP departments.
"If the DUP does take a unilateral approach, disregarding the authority and joint nature of the executive office on an issue which is cross-cutting, with massive budgetary implications and which is undermining public confidence in the political institutions, this will have grave consequences," he said.
Claims of widespread abuse include a farmer allegedly set to pocket around £1m (€1.19m) in the next 20 years for heating an empty shed.
In an extraordinary TV interview, a tearful Mr Bell said God told him to come clean but Ms Foster demanded he keep the RHI open for an extra fortnight despite its huge losses.
Back in 2010, the then first minister, Peter Robinson, stood aside while allegations concerning his wife were investigated.