Carillion shares earlier plunged 30 percent to a new low after Sky News reported the company had put administrators on standby and the government said it had held a crisis meeting over the fate of the business - a major provider of public services employing around 43,000 people.
A spokeswoman for the Pension Protection Fund said it was "aware of the discussions between the company, government and banks and, along with the trustees and the Pensions Regulator, will act as it always does to protect the interests of Carillion scheme members and levy payers".
"As Carillion is a major supplier to government, it should come as no surprise that we are carefully monitoring the situation while working to ensure our contingency plans are robust".
Ministers reportedly discussed the contingency plans in place should Carillion collapse, news of which first emerged on Wednesday during Cabinet Office orals.
Unions have also urged the Government to step in to protect 19,500 jobs that are now at risk.
Carillion's large syndicate of lenders includes Barclays, HSBC and Santander UK, as well as a host of overseas firms.
"Without that commitment of support from the government, administration is all but inevitable", the source said.
A number of disposals aimed at raising cash, including that of its Canadian operations, are progressing more slowly than originally anticipated.
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The court agreed to hear it on Friday itself and marked it to the bench of Justices Arun Mishra and Shantanagoudar. Another party leader and senior lawyer Abhishek Singhvi, who was also not in Delhi, was also consulted.
In November, Carillion reported full-year profit will be "materially" lower than expected after it experienced a combination of delays to disposals of certain public-private partnership deals, and a "slippage" in the start of a "significant" project in the Middle East in addition to lower-than-expected margin improvements across a "small" number of United Kingdom support services contracts.
Unite assistant general secretary Gail Cartmail, said: "The government must consider all options while the future of Carillion hangs in the balance, including bringing contracts back in-house".
The Wolverhampton-based company - a major supplier to the Government and named among the firms awarded deals for the building of phase one of the HS2 rail line - is meeting lenders to discuss options to reduce net debt, recapitalise and/or restructure the group's balance sheet.
The Financial Conduct Authority (FCA) is investigating whether Carillion appropriately disclosed its financial position in the run up to a series of profit warnings issued in the past six months. In response, Carillion cut its generous dividend and its long-standing Chief Executive Officer Richard Howson - in the post since 2012 - resigned.
Mr Howson was replaced on an interim basis by Keith Cochrane, the former Weir Group boss, with Andrew Davies due to arrive from Wates Group as his permanent successor on 22 January.
However, it now has debt and liabilities including provisions, pensions and accounts payable of as much as 1.5 billion pounds, according to analysts, compared with a market value of just 68 million pounds on Friday.
A spokesman from Carillion declined to comment.