UPDATE 2-Carillion plunges on report administrators on standby

* Carillion has put administrators on standby - Sky

* Shares plunges 30 percent

* Government ministers meet to discuss plans

* Carillion has key role in public services (Adds background, details)

LONDON, Jan 12 (Reuters) - British building and services company Carillion has put administrators on standby in case it is unable to strike a rescue deal with creditors, Sky News reported, hitting shares in a business whose fate has triggered government crisis meetings.

Carillion shares plunged another 30 percent on Friday following the Sky report that it might seek protection from its creditors. Sky did not say where it obtained the information. Carillion was not immediately available to comment.

On Thursday, ministers overseeing everything from justice to transport, health and education met to discuss how they should respond to the possible demise of a company that plays a central role in British public life.

A spokesman for Prime Minister Theresa May said on Friday the government was monitoring the situation and had drawn up a contingency plan after the 200-year-old group asked creditors for more time to tackle its debts.

"Ministers did meet yesterday, there are ongoing meetings," he said.

One of many private companies to run public services in Britain, Carillion is fighting to survive after costly contract delays and a downturn in new business prompted a string of profit warnings and a first-half loss of more than 1 billion pounds ($1.4 billion).

Employing 43,000 people, it provides services to government departments including justice, health and education, and has built hospitals, roads and rail lines. It was also behind key construction projects including London's Royal Opera House, the Tate Modern gallery and the Channel Tunnel rail link.

In July last year it won contracts to build Britain's new High Speed 2 rail line, a key project that will better connect London with the north of England. The company also works in Canada and the Middle East.

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.

"We are monitoring this situation closely and will continue to do so," the prime minister's spokesman told reporters at a daily briefing.

Asked if the government could take over Carillion's public sector contracts, he replied: "Of course the government will make contingency plans for many different situations, as you'd expect."

The company met with creditors including RBS and Santander UK on Wednesday to ask them to consider a debt extension or roll-over in financing talks and it is expected to talk with the Pension Regulator on Friday.

Its pension deficit stands at around 580 million pounds.

Many of Britain's service providers have been hit in recent years after they took on work during the financial crisis at low prices for long-running, fixed-price contracts to keep work coming in.

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.

($1 = 0.7333 pounds) (Additional reporting by David Milliken; Editing by Paul Sandle and Mark Potter)