The Wolverhampton-based firm met with key stakeholders, including the government, over the weekend to attempt to tackle its £900m debt and £587m pension deficit, as well as strengthen the group's balance sheet.
The lenders pulled out after the government refused to guarantee the firm's debts, leaving Carillion without the cashflow required to continue as a business.
"But the contracts were awarded after the warnings about Carillion were out there in July a year ago yet there was supposed to have been a process of due diligence".
The Prime Minister's spokesman insisted the Government had "kept a very close eye" on the firm but admitted there may be "lessons which can be learned".
Carillion said that it anticipates that the official receiver will make an application to the High Court for PricewaterhouseCoopers LLP to be appointed as special managers to act on behalf of the official receiver.
Now questions are being asked about what is next for the contracts the firm had with Westminster, including many with the Department for Transport.
Labour leader Jeremy Corbyn used the collapse to call for an end to "rip-off privatisation policies" which he said had "fleeced the public of billions of pounds".
Tim Roache, the general secretary of the GMB Union, said the Conservative government was "asleep at the wheel" when it continued to award work to Carillion despite its profit warnings.
"This is a watershed moment".
Nearly half of them are in the United Kingdom, though Carillion also has a presence in the Middle East, Canada and the Caribbean.
The government defended its position on Monday, with the Prime Minister's spokesman telling journalists: "It's regrettable that Carillion has not been able to find suitable financing options with its lenders. but taxpayers can not be expected to bail out a private company".More news: AMD releases update for Windows with Spectre security vulnerability fixes
Mr Lidington revealed Carillion's former bosses will be investigated as he warned of possible "severe penalties".
Carillion retirees already receiving their pensions will continue to receive payments, the government has assured.
THERE are concerns over the jobs, pay and pensions of thousands of workers following the "disastrous" news that Carillion has gone into administration.
How did Carillion go bankrupt? It is understood that the Durham contract with Carillion may not expire until 2019, and Carillion still appears to have an involvement in the Rochdale contract. "The government has announced that it will continue to deliver all public sector services following the insolvency of Carillion and this should mean that services provided to schools continue without any problems", Julia Harnden, ASCL funding specialist.
Beresford added, "Many large regional contractors miss out on work simply because they are not among the usual suspects".
The government has told Carillion employees to go to work as normal and confirmed that they would be paid.
The Scottish Government has said contingency plans are in place for major contracts north of the Border affected by the liquidation of Carillion.
This is the full list of questions published by Jon Trickett, shadow cabinet office minister, over the collapse of outsourcing giant Carillion.
They said the government had the legal right to appoint a "crown representative" to work with a supplier deemed to be at risk to improve its performance, but that this had not been done.