Image source, PA

Transport for the North, a partnership of 19 local authorities and business leaders, said it is working with the DfT, Network Rail, Rail North and the train operating companies to mitigate against the impact of Carillion's liquidation.

Chief executive Barry White said Transport for the North is concerned about potentially longer-term problems such as delays to engineering/upgrade works.

He added: "With engineering programmes such as the Bolton corridor being among those that were being carried out by Carillion, we will be looking closely at developments to see what can be done to ensure any impact is minimised.”

Here is a look back over the collapse of Carillion over the last six months, as seen through its share price.

The company suffered a corporate heart attack on 14 July, when it issued a huge profit warning.

Carillion went on to be awarded three big government contracts - worth a total of £2bn - despite issuing another two profit warnings.

Image source, Getty Images

Intrastructure group Balfour Beatty has said Carillion's collapse could cost it up to £45m.

Balfour is working with Carillion in joint ventures on three projects: the Aberdeen Western Peripheral Route, the A14 in Cambridgeshire and the M60 Junction 8 to M62 Junction 20 scheme.

The company said it would continue to work with its customers and would meet its contractual commitments, but Carillion's failure was likely to cost it between £35m and £45m this year.

The news sent shares in Balfour Beatty down 2.5%.

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Image source, Reuters

The Conservative head of an influential MP committee is calling for an inquiry into Carillion's collapse, as are Labour and the Liberal Democrats.

Bernard Jenkin, chair of the Commons Public Administration Committee, says "nobody's blameless" in the firm's demise.

"I think the whole of government is going to be implicated, the civil service as well. I think the Secretary of State wouldn't have let these contracts against official advice," he said.

"Nobody's blameless, we've all got blood on our hands. Let's see what we can learn positively from this situation rather then just doing the blame game," he added.

Image source, Getty Images

Speedy Hire, a provider of equipment and support for construction companies, has seen its shares fall by more than 8% after Carillion's collapse.

Carillion is one of the company's biggest clients, and its demise has left Speedy Hire heading for its biggest share price fall since 2015.

Analysts at stockbroker Liberum said the news was "unhelpful but not as bad as feared" for Speedy Hire.

That's because investors expect Carillion's partners to take on much of its workload, they said.

Image source, Getty Images

In non-Carillion related news, Airbus has admitted that it may have to stop making the A380 super jumbo jet unless it wins more orders.

The minimum number of A380s that Airbus is prepared to build is six per year.

Emirates, the Middle East airline, is the biggest customer for the huge passenger jet.

Airbus chief operating officer John Leahy said: "We are still talking to Emirates and quite honestly they are probably the only one in the marketplace who can take a minimum of six A380s a year for a period of eight to 10 years,

"If we can't work out a deal with Emirates I think there is no choice but to shut down the program."

Labour's shadow business and trade minister echoes concerns about the hundreds of small businesses who rely on work from Carillion...

Image source, Reuters

It is vital that Carillion’s small business suppliers are paid what they are owed, according to Mike Cherry, chairman of the Federation of Small Businesses.

Otherwise those companies could also "be put in jeopardy", putting even more jobs at risk on top of Carillion’s own 20,000 UK employees, he said.

Unpaid bills from Carillion may "go back several months", he said, after evidence the company was making small suppliers wait 120 days to be paid.

"When the dust settles on this sorry saga, there is also a wider lesson to learn about the concentration of public contracts in the hands of a small number of very big businesses," Mr Cherry added.

Image source, Getty Images

Carillion's competitors have been given a boost on the stock market after the construction and services firm collapsed.

Healthcare group Serco, which bought £47m in healthcare contracts from the crisis-hit company in December, is the biggest winner, rising 4.7%.

Among other former rivals, G4S rose 1.6%, Interserve gained 1.3%, while construction firms Balfour Beatty and Kier Group rose 0.3% and 1% respectively.

"People will pick up business and for some it will be good," an analyst at a UK stockbroker told Reuters.

Image source, Sellafield Ltd

The huge multinational firm Carillion, which went into liquidation this morning, was involved in projects at Sellafield, but only on a small scale, staff at the nuclear reprocessing plant say.

A spokesman said the firm was part of a joint venture involved with recovering material from old waste stores.

"There are fewer than 10 members of staff from Carillion on site working on that project and Sellafield is confident that project can continue without any financial impact or delays," he said.

Gavin Bevis
BBC News

John Mann, Labour MP for Bassetlaw, has described the collapse of Carillion as "an opportunity to close down expensive, inflexible contracts and bring them back into the public sector".

He cited the East Leake schools PFI contract run by Carillion as the sort of deal that should be immediately brought in-house.

He wrote on Twitter, external: "Here’s a great idea: put a construction company in charge of school meals and running prisons. Oh, it’s just gone wrong. What a surprise."

Image source, Getty Images

Theresa May's de facto deputy, David Lidington, has said Carillion's troubles "arose for the most part from a side of the business that is nothing to do with UK government contracts".

Image source, Reuters

Commenting on Carillion, Rehana Azam, national officer of the GMB union, said: "The fact such a massive government contractor like Carillion has been allowed to go into administration shows the complete failure of a system that has put our public services in the grip of shady profit-making contractors."

She said: "There is no place for private companies who answer to shareholders, not patients, parents and service users in our public services. What's happening with Carillion yet again shows the perils of allowing privatisation to run rampant in our schools, our hospitals and our prisons."

Image source, Getty Images

Theresa May's de facto deputy, David Lidington, has said Carillion's troubles "arose for the most part from a side of the business that is nothing to do with UK government contracts".

The first big sign that Carillion was in peril came in July, when the firm wrote off £845m in income it had previously expected from major contracts.

Of that, £470m came from overseas markets and the rest related to the UK.

The majority of the foreign income was in Canada and the Middle East, where some clients with big contracts appear to have been slow to pay their bills or to have not paid at all.

The Middle East accounted for 13% of the firm's income. At the time, Carillion said it would pull out of construction markets in Qatar (pictured), Saudi Arabia and Egypt.

Image source, PA

If Labour were in power, would they have bailed out Carillion?

No, they wouldn't have used taxpayer money to save the business, says the party's shadow business secretary Rebecca Long-Bailey.

Instead, the public sector contracts should be taken back under government control to give certainty to Carillion workers, others in the supply chain and those who rely on the firm's pension fund, she says.

There needs to be a "seamless transition" for the services in health, education, justice, defence and transport that Carillion provided, she adds.

The construction firm is to be liquidated after its huge financial troubles finally overwhelmed it.

The UK's second biggest construction firm was involved in hundreds of contracts in the UK and beyond.

Here are some of the big ones:

• HS2 and Crossrail
• Battersea Power Station
• Hundreds of UK schools
• NHS services
• Library of Birmingham
• Liverpool's Anfield football stadium
• Aberdeen Bypass
• Projects across the Middle East and Canada

Victoria Derbyshire

The collapse of Carillion is a "crisis of the company's making", says Mike Lynch, assistant general secretary at the Rail, Maritime and Transport (RMT) Union.

Some of the directors should be held accountable, particularly after dividends were paid out to shareholders last year amid the firm's financial difficulties, he told the BBC's Victoria Derbyshire show.

RMT is calling on rail companies which had contracts with Carillion, like Network Rail, Heathrow Express and Arriva Rail, to take those contract workers in-house to give them secure employment.

Image source, Getty Images

Oxfordshire County Council has left nothing to chance in the event of Carillion's collapse.

Carillion provides school dinners to around 18,000 students in Oxfordshire.

The council says that if Carillion staff don't turn up today "we will provide school lunches to schools needing support, and the fire service are on standby to deliver them".

Alexandra Bailey, the council’s director for property, assets and investment, said the contracts with Carillion are being taken back in-house.

Today Programme
BBC Radio 4

Image source, Graham Eva

Labour's shadow business secretary Rebbeca Long-Bailey (pictured, right) says there are "extreme concerns over the government's handling" of Carillion's contracts.

"There were three profit warnings in the last six months yet the government in that time awarded three extra contracts worth £2bn," Ms Long-Bailey told the Today Programme.

That's despite it being government policy to designate a company as high risk, and to re-consider issuing contracts, if the firm issues a profit warning, she said.

Ministers should hold a full and transparent investigation - not just into the activities of the company, but the activities of the government itself, she added.

Theresa May's de-facto deputy, David Lidington, said the government made sure Carillion's partners could take over those contracts if the firm went under.