Drawing the Economy Committee sitting to an end, chair Steve Aiken says there has not been "appropriate communication" on the part of the department.

"We need to be much more joined-up," he says, adding that openness from the department is "essential" for effective governance and scrutiny.

Simon Hamilton says there was "no attempt not to share information" over the RHI scheme, but he says the department will learn lessons on that point.

The committee agrees to "note" the legislation rather than approve it as it has not had sufficient time to scrutinise the cost mitigation plan.

Ulster Unionist Alan Chambers says the RHI debacle will hurt confidence in Northern Ireland "as a place to invest on an international basis", particularly those from the United States.

"It is going to damage our reputation," he says.

The North Down MLA  questions the "100mph rush" on approving the RHI cost-cutting plan, and warns that the assembly is on "dangerous ground".

He touches on the mater of fraudulent use of the RHI scheme, to which Dr Andrew McCormick says there is no sign yet of any "prima facie evidence of intent to deceive", but investigations are continuing.

Stormont's Economy Committee is being asked to take a "major leap of faith" in its rushed scrutiny of the RHI cost-cutting plan, Alliance Party MLA Stephen Farry says.

He asks what the Department for the Economy defines as an "abuse" of the scheme, which would be targeted in a crackdown by officials.

Dr Andrew McCormick says beneficiaries of the scheme must be able to show they have a "valid use for the heat" and they are using their boilers "in a reasonable way".

"Just consuming heat for the sake of securing payment is not eligible," he says.

He says the plan the department has come up with is the "best available" when various factors - "cost, value, control and [EU] state aid [rules]" - are taken in to consideration.

An important insight here - Economy Minister Simon Hamilton tells the committee that entitlement to RHI subsidy payments is solely dependent on the performance of the boiler purchased as part of the scheme.

Image source, Thinkstock

So, if a boiler fails due to overuse, for example, the owner and beneficiary of the scheme will no longer receive a subsidy as part of the RHI scheme.

Under questioning from the DUP's Gordon Dunne, Dr Andrew McCormick gives "absolute commitment" that the Department of the Economy will "learn lessons" from the RHI scandal.

The DUP's Gordon Dunne asks about the position of those who signed-up for the RHI scheme, "considering the outlay they have had".

Mr Hamilton accepts that "ordinarily" the proposals would have been subject to public consultation and other types of scrutiny.

Mr Dunne also asks what the new return for beneficiaries would be under the cost-cutting plan - currently, claimants receive about £1.60 for every £1 of fuel they burn.

The economy minister says that "in terms of fairness and return", the regulations that are before the committee have "brought that return back to a range of around 12%".

The minister's DUP colleague Gordon Lyons welcomes the proposals and says the "real public anger" has come from the "allegations of abuse and waste and fraud".

Sinéad Bradley of the SDLP says MLAs "are being asked to blindly walk into this".

She says the "natural thing to do" would be to "look into good practice, and we are far outside good practice".

The flames of the RHI scandal continued to rise over the Christmas and new year period, and finally threatened to burn the house down at Stormont last week.

Martin McGuinness tendered his resignation as deputy first minister as of 17:00 last Monday, taking the political institutions to the brink of caving in and leaving an election an inevitability.

He said his decision had been taken primarily because of the DUP's handling of the RHI scheme, but he listed other factors - including a DUP minister's cutting of funding for an Irish language scheme - as reasons why his hand was forced.

"Today is the right time to call a halt to the DUP's arrogance," he said, adding that people should be allowed "to make their own judgement on these issues democratically at the ballot box".

With Mr McGuinness quitting, Arlene Foster lost her role as first minister, and she hit back by saying his move was "not principled".

"Because of Sinn Féin's selfish reactions, we now have instability," she said in an address she posted on her Facebook page.

Since then, her party has announced its desire for a public inquiry into the RHI scheme, and has reversed the decision to cut funding for the Líofa Irish language scheme, that had so riled Sinn Féin.

Mrs Foster warned that an election will be "brutal", but that has not been enough to satisfy Sinn Féin and pull it back from its insistence that an election must take place.

Chair Steve Aiken asks about possible legal challenges to the proposals to cut the RHI scheme's costs.

He asks the economy minister and the permanent secretary if they will resign in the case that there is a strong legal ruling against the proposal.... and the two men smile.

Simon Hamilton says they are "confident of the legal opinion" and they "absolutely" expect the proposal to be challenged.

He makes light of the question regarding resignation by saying: "I may not be in a position to resign from anything."

On the question of the Department of Finance's view, Mr Hamilton says that "as of now" ... the proposals do not have approval of Finance Minister Máirtín Ó Muilleoir.

In a bid to deal with the growing crisis, the assembly was recalled for an emergency sitting just before Christmas... and it's fair to say there were some extraordinary happenings up here on the hill.

Members of the assembly angrily walked out of the chamber twice when Arlene Foster gave a ministerial statement without the support of then Deputy First Minister Martin McGuinness with whom she shared joint office.

Later in the day, Arlene Foster faced a vote of no confidence in her position as first minister, but she she he would resist her opponents' "fevered quest" to build her "political gallows".

Speaker Robin Newton, a DUP MLA, found himself at the eye of the storm and was widely criticised by politicians over allowing Mrs Foster to make her statement without the support of the deputy first minister... and the fallout from that will continue later today, when he will face a vote of no confidence.

Image source, Press Eye

December saw the RHI scandal sweep along at a rapid pace.

Former enterprise minister Jonathan Bell (below) made sensational allegations in an interview with the BBC's Stephen Nolan regarding the role of Mrs Foster and top DUP advisers.

He said the aides "intervened" to prevent the closure of the scheme at a crucial time, and had it been shut down when he had asked for, the projected extra £490m cost to taxpayers could have been avoided.

Image source, PA

He also alleged that they tried to "cleanse the record" of references to Arlene Foster (below) and her department.

The advisers denied the claims and Mrs Foster also distanced herself from any wrongdoing.

The first minister faced calls for her resignation over her role in the project - including from then Deputy First Minister Martin McGuinness - and virtually every other party at Stormont called for a public inquiry into the matter.

So, just what is the Renewable Heat Incentive (RHI) scheme, and how has it led Stormont to yet another crisis point? Let's go right back to the start...

The RHI initiative was introduced in 2012 by the Department of Enterprise, Trade and Investment (Deti), then led by Arlene Foster, with the aim of increasing the uptake of renewable heat technologies.

But in July last year, the Northern Ireland Audit Office stated in a report that "serious systematic failings" in the scheme are likely to cost the Northern Ireland budget "hundreds of millions of pounds".

Image source, Tchara

The Audit Office investigation was prompted when a whistleblower contacted the Northern Ireland Executive in January, alleging that the scheme was being abused.

One of the claims was that a farmer was aiming to collect about £1m over 20 years from the scheme for heating an empty shed.

At an initial Public Accounts Committee (PAC) inquiry session, a senior civil servant apologised for the department's lack of oversight in the scheme and said that by the end of it, it will have cost the public purse a grand total of £1.18bn.

In November, the SDLP's Daniel McCrossan said the scandal was "one of the biggest" that politicians had encountered since devolution.

Mr Hamilton says his Department for the Economy is relying on "good, sound, robust legal advice" in drawing up its RHI cost-cutting proposals.

On the subject of the "legitimate expectation" of those taking part in the scheme, he says "no-one should be in expectation of a super-return".

In reply to a question from chair Steve Aiken, Dr Andrew McCormick says "there's quite a large proportion [of RHI scheme beneficiaries] who are getting a very high rate of return".

The minister sas the proposal is for a one-year period "to turn off the tap" in public expenditure and to allow for a consultation.

Economy Minister Simon Hamilton outlines his proposals to mitigate the projected £490m overspend of the RHi scheme.

It will entail bringing in a tiered system of tariffs "at the start of the financial year" 2016-17, he tells the committee.

"I think we can really bear down on things in terms of enforcement," the minister adds.

Steve Aiken says he is "extremely disappointed" that the Sinn Féin members of the Economy Committee are absent for this morning's meeting, adding that it is a "derogation of duty".

The DUP's Mervyn Storey declares an interest in the RHI scheme as member of a church that benefits from the scheme.

He picks up on the word "arrogance" used by Mr Aiken in his introduction to the meeting, saying the chair is making a political point.

Mr Aiken withdraws the word "arrogance" and reassures the committee of his impartiality on the matter.

Up and running a bit later than was scheduled, the Economy Committee begins with deputy chair, the Ulster Unionist Steve Aiken (below), chairing this morning's meeting in the absence of usual chair Conor Murphy of Sinn Féin.

Economy Minister Simon Hamilton and his permanent secretary Dr Andrew McCormick arrive to brief the committee on their plan to cut the costs linked to the botched RHI scheme.

So, what's on the cards today? Here's a look at what will be coming up in the chamber, external from midday...

One thing that's almost certain is that we'll probably be here for a lot longer than those indicative timings suggest.

Image source, NI Assembly

Debates on legislation have no time limit, so expect plenty of MLAs to have a long say on both the matters that appear under executive committee business on the above table... particularly those RHI scheme regulations.

Whatever way it all pans out, we'll be here to the last!

Mark Devenport
BBC News NI Political Editor

Assembly elections are set to be called by the Northern Ireland secretary later if Sinn Féin fails to nominate a deputy first minister to replace Martin McGuinness.

He quit last Monday after DUP leader Arlene Foster refused to stand aside as first minister while the botched RHI energy scheme was investigated.

Because they hold a joint office, the resignation automatically put the DUP leader out of her job, and elections must be called if the positions are vacant for seven days.

The DUP is expected to re-nominate Mrs Foster as first minister shortly after 12:00, but Sinn Féin is adamant it will not put forward a replacement for Mr McGuinness.

First up this morning, Simon Hamilton brings his plan to mitigate the £490m cost of the controversial Renewable heat Incentive (RHI) scheme before the assembly's Economy Committee.

The so-called cash for ash scheme is one of the major reasons why Stormont finds itself on the brink, and the economy minister has produced amending legislation that would reduce tariffs paid to about 1,800 people who got into the scheme before November 2015.

Over the weekend, Mr Hamilton was invited to appear before the committee along with his department's permanent secretary Dr Andrew McCormick.

They will answer questions on the cost-cutting plan, which has already been met with opposition from an organisation representing claimants of the RHI scheme, which says it would be "catastrophic" for businesses and would only add to the cost to the taxpayer.

Welcome along to our Stormont Live coverage of what is a critical day for the political institutions in Northern Ireland and one that will be brimming with drama.

Stormont is highly likely to have collapsed by the end of play, with an election all but guaranteed to be called after that, and you can follow everything that happens up here on the hill with us right throughout the day.