A DUP special adviser [Spad] pressurized officials to keep Stormont’s botched green energy scheme open even though he knew costs were surging out of control, a government official has claimed.

The explosive revelation came as senior civil servant Andrew McCormick gave evidence to the assembly’s spending watchdog inquiry into the Renewable Heat Incentive (RHI).

The Department for the Economy (DfE) permanent secretary told the Assembly’s Public Accounts Committee (Pac) that inside information about potential curbs on the scheme’s generous subsidies had been leaked ahead of a spike in applications in November 2015.

When pressured by Alliance MLA Trevor Lunn over whether influence had been brought to bear on officials to keep the scheme open, Mr. McCormick said even though he did not have direct evidence, he understood Arlene Foster’s former adviser Andrew Crawford was the person who influenced the decision to keep the RHI running.

The Irish News revealed last month that Mr. Crawford’s brother James is a Co Tyrone-based poultry farmer and RHI claimant. James Crawford, who is among some 800 poultry farmers claiming the lucrative subsidy, expanded his chicken business in Beragh near Omagh in 2014-15.

The scheme was set up by Mrs. Foster in 2012 when enterprise minister and Mr. Crawford was her then adviser.

He is now a special adviser to DUP agriculture minister Michelle McIlveen. Last night, he insisted he would only have offered “informal advice” and that he did not attempt to prevent the scheme’s costs being curbed.

Mr. McCormick said he was making no suggestion Mrs. Foster became involved in keeping the scheme open.

He told MLAs that when concerns about the cost of scheme were first raised in mid-2015, those within The North’s renewable heat industry became aware of plans to end its generous subsidy, which likely led to a massive influx of RHI applications.

“Around the period of July there is evidence of some premature information being made available to the industry,” he told the Pac.

Although civil servants did not realize at the time how serious the consequences could be, he said their evidence had subsequently emerged that the industry had been asking others in the “political class” to delay cost-saving measures.

“The consequence is very serious because this shows that there was premature awareness of the potential for the tariff to be reduced and the message went within the sector – ‘get in quick’,” Mr. McCormick said.

He said because the RHI was originally supposed to be entirely funded separately by the Treasury, there was a misconception that it would not impact on Stormont’s budget.

He said it was possible some of the pressure to keep the scheme running came through others in the DUP via former economy minister Jonathan Bell’s special adviser, Tim Cairns.

“That is purely inference, I have no evidence for that, it just seems a not unreasonable inference that that might have happened,” he said.

He said the decision to delay a reduction in the tariff and the influence of Mr. Bell’s adviser created the conditions for the overspend, the “perfect storm”.

He admitted officials were “blind” to the consequences.

In another shock revelation during the lengthy PAC hearing, Mr. McCormick said his meeting with Mr. Bell last month, where the former DUP minister had sought to “exercise his prerogative as a former minister” to review departmental papers, may have been secretly recorded.

The permanent secretary said he had heard the meeting was taped but “without my knowledge or consent”.

Sinn Féin’s Oliver McMullan said the DUP’s handling of the RHI crisis had “damaged public confidence and the integrity of the political institutions”.

“There needs to be full accountability in relation to the RHI scandal and the allegations of corruption. There must be no hiding place for those who abused the scheme,” he said.

SDLP leader Colum Eastwood said: “His suggestion that insider information played a part in the Renewable Heat Incentive (RHI) catastrophe is a signal of a corruption in this scheme and a corruption of government that must be rooted out.”