It is "quite shocking" to suggest ministers ordered that minutes of meetings involving them should not be taken, says Mrs Foster.

David Sterling (below), the head of Northern Ireland Civil Service, has told the inquiry that the "common view" of senior officials across the Northern Ireland Executive departments was that the "good practice" of note-taking at meetings with ministers had "lapsed".

Image source, RHI Inquiry

Mrs Foster says she wasn't aware of that, she doesn't believe her fellow ministers were either and she would've expected her decisions "to have been recorded somewhere".

It's one thing to say minutes were not being made about who said what, she says, but "it's quite a different thing to say that we stopped recording ministerial decisions".

"Not once did I tell officials not to take minutes," she adds.

Inquiry chair Sir Patrick Coghlin returns to the "basic issue, which is did this happen or did it not happen".

He explains that DETI's energy boss Mrs Hepper has told the inquiry that it was raised with the department's second most senior official David Thomson, who can remember the discussion about the scheme's legal risks.

Image source, RHI Inquiry

Sir Patrick says: "If Fiona Hepper was making it up that the conversation with you took place," he tells Mrs Foster, "that seems a pretty risky hostage to fortune that she would've had to face Mr Thomson who might've said: 'Well, what did the minister say?'

"That sees to me quite a potent factor in deciding whether or not come form of communication took place."

Mrs Foster reiterates that if the call did take place the issue "must've been significantly played down for me not to have reacted in the way that I think I would've reacted".

A plan by the UK government department that was running the Great Britain RHI scheme to add cost controls to its initiative was not drawn to Mrs Foster's attention, she says.

In March 2012, the Department of Energy and Climate Change (DECC) proposed a temporary suspension of its scheme if it was thought the there was a risk of an overspend.

Image source, PA

In a document outlining the plan, DECC said the cost control was needed to ensure the "long-term future of the RHI" and keep its spending under control.

Uptake was low at the stage, he acknowledged, but the budget protection measure considered as a fallback in case the demand later took off.

Mrs Foster says she would remember if she'd been made aware of the plan because it was "quite a significant issue, I have to say" and it was not provided to her in a ministerial submission.

In her witness statement, Mrs Foster says that if she'd been told of Ofgem's warning about the legal risks of the RHI scheme they must've been" significantly downplayed".

When that was put to Mrs Hepper in February, she said she had a clear memory of the meeting and didn't "believe it was downplayed in any way".

Image source, RHI Inquiry

Asked now for her reaction to Mrs Hepper's evidence, Mrs Foster says the official seems to have a "very clear memory" of the discussion but not whether it was a phonecall or a meeting.

If it had been a meeting it would have been recorded in her electronic diary "and it's not".

Image source, RHI Inquiry

Mrs Hepper (above) has told the inquiry that she "sought a word with the minister" regarding Ofgem's legal warning about the RHI scheme and it was most likely to have been a phonecall.

She said she "outlined the detail of the issue" to Mrs Foster and they discussed "the consequences" of stopping the scheme's progress to amend the scheme.

But she says the minister was "content" that the scheme would be opened as planned and the changes could wait until later.

Mrs Foster says that if she had discussed the "stark" warning from Ofgem about the legal risks with the RHI scheme she would've remembered it.

"This was a very big deal and I have absolutely no recollection of having a discussion with Mrs Hepper either on the telephone or in person."

Image source, Getty Images

She says that if it did take place she "wasn't warned in stark terms that I had to make a decision as to whether to proceed or not with the scheme".

"I certainly would recall that - this was a scheme that was about to go live."

She adds that if she'd been told about it she'd have then talked to her adviser Dr Crawford about it because "it was not a decision... I would've taken on my own" but she can't remember any discussion with him either.

In her evidence, DETI's energy boss Fiona Hepper says Ofgem's advice about the legal risks with the RHI scheme was relayed to the minister.

But Mrs Foster says she never received the warnings and didn't ask officials to proceed with a project that was "inherently flawed".

Image source, RHI Inquiry

She tells the inquiry she would have expected to have been told about the alerts because "this was a pretty fundamental warning".

The former minister says her diary shows no evidence of any meeting taking place with Mrs Hepper regarding the matter.

Lawyers for Ofgem - the organisation administrating the RHI scheme - warned DETI in June 2012 that there were legal risks with the initiative's regulations and they advised that the department should hold off on opening it until those were amended.

But DETI told Ofgem that the scheme couldn't be delayed because there was a "commitment" with the minister that the scheme had to open by the end of September that year.

DETI's energy boss Fiona Hepper - who conveyed that message to Ofgem - told the inquiry she was given that direction "in discussions" with Mrs Foster.

Asked about that, Mrs Foster says she has "no recollection" that she ordered the scheme to open by the end of September.

She says the energy industry had been asking question about when the scheme would be up and running but she insists that there was no "aggressive" pressure on her to open it quickly.

Image source, RH Inquiry

Mrs Foster says it's not for her to say whether officials deliberately misled her but she had nevertheless been misled "in a particular direction".

"It would be wrong for me to say that [it was deliberate] when I don't know what the motivations were," she adds.

Mrs Foster's ministerial adviser told the inquiry on Monday that he and the minister were "misled" by civil servants in relation to the cost of the RHI scheme because information in financial assessments hadn't been fully relayed to them.

Dr Andrew Crawford (below) also suggested that officials had done that deliberately.

Image source, RHI Inquiry

Mrs Foster says she wouldn't use the term "misled".

"We weren't given the information and I can't quite understand why we weren't given the information, but I can't attribute why because I simply don't know," she says.

Image source, Getty Images

Asked if there was any guidance or training given to Stormont ministers on the public expenditure rules, Mrs Foster says minsters get a first-day brief but there is no training in managing public money.

She says that "would be very helpful" to ministers "after this whole sorry story".

Image source, RHI Inquiry

Mrs Foster is asked if she agrees that she wasn't in a position to make a "fully informed and objective assessment" about the costs and benefits of the RHI scheme.

She says she had assurances from the Treasury that the full costs of the similar RHI scheme in Great Britain would be covered.

"I took it that that was going to be the same case with the Northern Ireland scheme as well, albeit that I didn't have a clear enumerated idea of what that would be," she adds.

Mrs Foster rejects the suggestion that she signed a "blank cheque" for the RHI scheme.

She says that officials should've given her more information about the costs of the initiative.

Image source, Getty Images

"I did read the information that was give to me, I took that information at face value," she tells the inquiry, adding: "I don't accept that it was a blank cheque at that time."

But inquiry panellist Dr Keith MacLean says that even a rough assumption on Mrs Foster's part on the basis of the figures she did get would've led her to realise that the cost would be at least "a quarter-of-a-billion pounds".

He says the fact that the Treasury was going to cover the spend "doesn't mean that it's good value or that it balances out the benefits".

In April 2012, Mrs Foster signed off on a declaration that she was satisfied that the benefits of the RHI scheme justified the costs.

Asked about what she understood the costs to be at that time, she tells the inquiry that she believed it was £25m over four years.

Image source, Getty Images

But she accepts that she didn't know that the overall cost would run to hundreds of millions of pounds in subsides over the 20-year lifetime of the scheme.

She adds, though, that she had confidence from her officials that the Treasury would cover whatever that total would be.

It is "difficult to understand" why a proposed monitoring board for the RHI scheme was never set up, says Mrs Foster.

The administrator for the scheme agreed with the Department of Enterprise, Trade and Investment (DETI) that a joint panel would be established to help keep an eye on the initiative, scrutinising and controlling its operation, costs and uptake.

Image source, Getty Images

But it was never set up, even Mrs Foster was informed that it would be.

She says she would have expected it to be put in place but she "cannot understand" why that didn't happen.

"I don't accept the narrative that says I should've been checking the homework of officials to make sure things happened."

She's already taken the oath, so it's straight into the questions for Arlene Foster.

The inquiry's senior counsel David Scoffield QC kicks off the day's questions.

Image source, RHI Inquiry

He clears up some issues around Mrs Foster's newly-discovered diary from June 2011 and then turns to the scheme's regulatory impact assessment of April 2012.

You can findMrs Foster's written statement on the inquiry's website, external.

Mrs Foster was the minister at Stormont's Department of Enterprise, Trade and Investment (DETI) when it set up the RHI scheme in 2012 and in that role she signed off on the project.

A key question for the RHI Inquiry panel will be whether or not she was aware of key information regarding the scheme when she approved it.

Image source, Pacemaker

When the scale of the scandal emerged in December 2016, there were widespread calls for her to resign to allow an investigation to be carried out into what went wrong.

She refused and has consistently denied any wrongdoing in relation to the scheme.

BBC News NI

Image source, Pacemaker

The judge chairing the inquiry suggested to Arlene Foster on Friday that she seemed to be heading up a "dysfunctional department" when the RHI scheme was being set up.

Sir Patrick Coghlin said it appeared "incontrovertible" that her trust in two key people she had relied on had been "completely unfulfilled".

BBC News NI

A former DUP ministerial adviser told the inquiry he did not send a confidential RHI scheme document to his poultry farmer cousin in order to advantage him.

Dr Andrew Crawford apologised for sending the consultation document, which was still in draft form and was not signed off by the minister Arlene Foster.

He accepted he should not have done it.

But Dr Crawford said the intention was not to help his family get into a scheme which was "too good to be true".

BBC News NI

An independent inquiry into the RHI scandal was established in January last year by the then finance minister Máirtín Ó Muilleoir.

He ordered it in the wake of the huge public concern and what was then a developing political crisis surrounding the scheme.

The RHI Inquiry began in November and Sir Patrick Coghlin (below), a retired Court of Appeal judge, is its chair and has been given full control over how it will operate.

Image source, Pacemaker

It will look at:

• the design and introduction of the RHI scheme
• the scheme's initial operation, administration, promotion and supervision
• the introduction of revised subsidies and a usage cap for new scheme claimants in 2015
• the scheme's closure

For more information on the RHI Inquiry, you can read our handy Q&A.