Construction giant Carillion is to go into liquidation, threatening thousands of jobs.
The move came after discussions between Carillion, its lenders and the government failed to reach a deal to save the company.
However, the government will provide funding to maintain the public services run by Carillion.
The firm is involved in major projects like the HS2 high-speed rail line, as well as managing schools and prisons.
Carillion is the UK's second largest construction company and has 43,000 staff worldwide - 20,000 in the UK.
It is not clear yet how those staff will be affected.
Some of Carillion's contracts will be taken on by other firms and some could be renationalised, according to BBC business editor Simon Jack.
"This is a very sad day for Carillion, for our colleagues, suppliers and customers that we have been proud to serve over many years," said Philip Green, Chairman of Carillion.
"In recent days however we have been unable to secure the funding to support our business plan and it is therefore with the deepest regret that we have arrived at this decision."
