The first minister is facing fresh calls to step down after it was revealed she wrote to banks encouraging support for the bungled Renewable Heat Incentive scheme.
In a letter to Northern Ireland’s leading banks written when the scheme was first set up, Arlene Foster - who was then enterprise minister – reassured bankers that payments would be guaranteed.
She also encouraged banks to “look favourably” on businesses that were seeking to borrow money for installing RHI systems.
In the wake of the latest revelations over the RHI fiasco, some of Mrs Foster’s political rivals have renewed calls for the First Minister to stand aside, while an investigation is carried out.
But the DUP has told the News Letter Mrs Foster will not be stepping aside “for a single day”.
Fatal errors in how the RHI scheme was set up have left Stormont facing a potential £490 million overspend bill over the next two decades.
Ulster Unionist leader Mike Nesbitt said: “As every day passes, further information emerges regarding Mrs Foster’s central role in what she herself told the Northern Ireland Assembly was the ‘debacle’ of the Renewable Heat Incentive.
“It is now clear she was warned in advance that there was a danger of ‘over incentivising’ the scheme, the very error she endorsed as Energy Minister.
“Once again, with no pleasure, I ask Mrs Foster to prioritise the future of the Stormont institutions over her role within them and resign. She knows it is the right thing to do for Northern Ireland.”
SDLP leader Colum Eastwood said the First Minister has “lost the confidence of the Assembly and of the public”.
He added: “ As further information comes to light relating to her specific knowledge about the detail and scale of the RHI scheme, the pretence that she was not across every ‘jot and tittle’ has lost all credibility. If Arlene Foster has done nothing wrong, as she claims, then she has nothing to fear from a public inquiry with full powers to compel witnesses and evidence.”
Mr Eastwood urged Mrs Foster to “listen to the will of the public” and stand aside.
Mrs Foster has remained defiant throughout the scandal in recent weeks and has rejected previous calls to resign.
In a series of tweets on Thursday, loyalist blogger Jamie Bryson claimed that senior DUP members would be holding a “crisis meeting” with Mrs Foster this weekend and she would be advised to step aside.
However, a DUP spokesman told the News Letter yesterday: “These tweets are complete and utter nonsense from a discredited source who was proven to be in cahoots with Sinn Fein to damage the DUP previously. There is not a shred of truth to any of them.
“Arlene Foster will not be stepping aside for a single day, nor has any such suggestion been made that she should.
“Her focus is on the proposals that will come forward in the New Year to reduce the burden on the public purse and she will not be distracted by political opportunists.”
A spokeswoman for the Department for Economy said the letter to the banks was “reasonable and appropriate” given the context facing the minister in January 2013.
She said the flaws with the scheme were not well documented at the time the letter was written.
“Indeed, the subsequent reporting of this matter has demonstrated that the impact of the tariff and the rate of return are complex and technical issues,” she added.
“When the then DETI Minister briefed lending institutions in January 2013 about renewable supports, the statement about the non-domestic RHI was entirely consistent with the Department’s then understanding, i.e. that the rate of return would be at a level of 12%.
“At that time, the Department had not recognised the much higher rate of return due to a misunderstanding that the tariff was lower than the market price. Indeed, action to encourage uptake was being considered as there was an underspend. Such action, including the letters to the banks, would have been entirely reasonable and appropriate, but for the design flaws in the scheme which had not been recognised by DETI at the time when these letters issued.
“The scheme, as set out in the letter would not have given rise to the problems about cost controls which were later experienced.
“Unfortunately, this was not how the scheme operated in practice due to errors back in 2012 which have already been detailed by the Northern Ireland Audit Office.”
TUV leader Jim Allister said the letters indicate “a far greater ministerial attachment” to the RHI than had been acknowledged before.
Meanwhile, last night Sinn Fein president Gerry Adams said that “the behaviour of the DUP has seriously damaged the credibility of the Assembly, Executive and the office of the First and Deputy First Minister”.
He described Assembly Speaker Robin Newton’s position as “now untenable” and added: “I hope that First Minister Arlene Foster is using this time to reflect on the crisis and that she will facilitate the sort of robust and thorough investigation that is required to deal with this scandal.”
However, Mr Adams pointedly stopped short of endorsing a full public inquiry – with the power to compel witnesses and documents – as colleagues Conor Murphy and Mary Lou McDonald had demanded.