The former directors are being pressed for more detail on points in their testimonies to the joint business and pensions committee inquiry, particularly where it appeared to contradict other evidence.

The directors had blamed a number of different factors for Carillion’s collapse on 15 January.

Rachel Reeves and Frank Field, who are chairing the inquiry into Carillion’s collapse branded the board earlier this month as “a series of delusional characters” who “maintained that everything was hunky dory until it all went suddenly and unforeseeably wrong”.

The Committees have now contacted the Federation of Small Business offering them the chance to respond to the dismissal by the Carillion directors of their evidence that Carillion were “notorious late payers” who “abused their dominant position” and left suppliers waiting for payment even beyond their extraordinarily long contracted payment terms.

Former CEO Richard Howson has been called upon to provide more detail about the structural beams at the Royal Liverpool Hospital whose design flaws were among the many factors ascribed some responsibility for Carillion’s downfall.

He has also been asked about his dealings on the Qatar contract – singled out for particular blame for the company’s demise –  and how much he was paid for his ongoing work in Qatar after he was removed as CEO.

Former finance director Zafar Khan has been asked to clarify again the terms of his departure, including whether a non-disclosure agreement was attached to it.

Meanwhile chairman Philip Green is asked about the “surprise” deterioration in the company’s cash flow shown in the September 2017 presentation that Zafar Khan stated had “spooked” the board and led to his dismissal.

Also Richard Adam, finance director between April 2007 – December 2016, is being called on to explain in more detail what he thinks happened to the “healthy” company he left, for it to go into compulsory liquidation a year later, and about acquisitions like Alfred McAlpine, which added £650m “goodwill” to Carillion’s books but otherwise held net liabilities of £50m.