The DUP says the First Minister "does not take her instructions from Sinn Fein, but from the electorate"
Sinn Féin's Martin McGuinness has called on Northern Irish First Minister Arlene Foster to 'step aside' during an investigation into a controversial green energy scheme.
Ms Foster set up the Renewable Heat Incentive (RHI) when she was Minister for Enterprise, Trade and Investment.
Opposition parties claim the British government faces a stg£400m (€477m) bill after overspending on the project.
The scheme at the centre of the scandal offered incentives to businesses for the installation of renewable heating systems, most of them burning wood pellets.
However, the subsidies exceeded the cost of the fuel - meaning the more fuel users burned, the more they could claim so it was drastically oversubscribed.
In a statement today, Deputy First Minister Martin McGuinness said he had spoken to Ms Foster by phone, and expressed "serious concern that the credibility of the political institutions is being undermined by the serious and ongoing allegations surrounding the design, operation, abuse and ending" of the RHI.
He explained: “This scheme has directly impacted on the public purse. Taxpayers’ money wasted in this scheme, needs to be retrieved. It is my belief the only way to establish the truth, and rebuild the reputation of the institutions, is to urgently establish a fully independent investigation into this matter.
“In addition, I also said that, in the public interest, she should stand aside from the role as First Minister while that investigation is underway and at least until an initial assessment had been concluded into the veracity of all the allegations."
He added: “That is what I would do if I was in this situation. I asked the First Minister to take the time and consider this suggestion carefully."
Responding to the statement, Ms Foster's Democratic Unionist Party said: "The First Minister will not be stepping aside, but instead is focused on ensuring the full facts about this issue emerge and proposals are brought forward which can make a significant reduction in the future financial burden the Executive would face.
"The First Minister does not take her instructions from Sinn Fein, but from the electorate.”
The Northern Assembly has been recalled from Christmas recess to discuss the scheme, and will meet on Monday.