A source briefed on the matter, who declined to be named, told Reuters that putting the cash-starved site under special administration could be the only option left to keep it afloat.
ArcelorMittal, the world's second largest steelmaker, owns 62% of ADI, and state-owned investment agency Invitalia has the remaining 38%.
The government statement said Invitalia was ready to inject some 320 million euros ($351.10 million) in ADI to raise its stake to 66%, but ArcelorMittal refused to offer guarantees on the additional investments ADI would need.
"The government has taken note of ArcelorMittal's unwillingness to make financial and investment commitments, even as a minority shareholder," the statement said.
It was released after Italian government figures, including Cabinet Undersecretary Alfredo Mantovano and Economy Minister Giancarlo Giorgetti, met in Rome with ArcelorMittal CEO Aditya Mittal.
Bogged down by an increase in energy prices and a drop in rolled steel coil prices, the steel plant has long been short of cash and has accumulated a huge debt pile with suppliers, particularly energy giant Eni.
Some 10,000 people directly work at the ex-Ilva steel works, based in the southern city of Taranto, while a further 6,000 are employed in related industries. Production was reduced in recent months, with some parts shut down and many workers on furlough.
The ex-Ilva plant has been a headache for successive Italian governments, as prosecutors have blamed it for producing highly toxic emissions, but is also an economic lifeline for a high-unemployment, depressed part of Italy.
($1 = 0.9114 euros)
(Reporting by Giuseppe Fonte and Angelo Amante, editing by Alvise Armellini; editing by Barbara Lewis)
