Toshiba has delayed the release of its earnings results again, sending its shares diving more than eight per cent, as it said it needed more time to investigate a possible accounting fraud at its loss-hit US nuclear unit.
Japanese media reports said the troubled firm would push back its financial results for another month, fanning fears the stock could be delisted from the Tokyo exchange.
Toshiba later issued a statement confirming it had filed a request with regulators for a deadline extension to April 11, the second delay for October-December results originally due in mid-February.
If the latest application is rejected, Toshiba will need to submit an earnings statement within eight business days, which would be on March 27, or face an embarrassing delisting.
The troubled industrial giant's shares tumbled 8.10 per cent to 197.5 yen (USD 1.72) by the break.
Japan's leading Nikkei business daily, quoting an unnamed source, said regulators would likely grant the request, but expressed reservations over the length of the extension.
"If you look at today's fall (in the stock price), market players are already pricing in a delisting," said Mari Iwashita, chief market strategist at SMBC Friend Securities.
Toshiba president Satoshi Tsunakawa will hold a news conference later in the day to address the announcement.
"For those who do not hold the shares now, they are standing on the sidelines in wait for the president's press conference" set for 4:00 pm (local time), Iwashita told AFP.
Investors "will be watching how the group plans to turn itself around and how quickly. They've been in a mess for years now so they need to act promptly".
Toshiba shares have been hammered this year, losing more than half their value since late December when it first warned of multi-billion-dollar losses at its US atomic subsidiary, Westinghouse Electric.
The firm has said a whistleblower had complained that one or more Westinghouse executives exerted "inappropriate pressure" on its accounting.
While it did not release earnings in February as scheduled, Toshiba warned it was on track to report a net loss of 390 billion yen in the fiscal year to March, as it faced a huge writedown topping 700 billion yen at Westinghouse.
The company today said it would need more time to look into the matter and assess its possible impact on earnings.
"An additional four weeks will be necessary to finalise the investigation," it added.
The crisis comes less than two years after Toshiba -- one of Japan's best-known firms employing about 188,000 people globally and reported annual revenue topping 5.6 trillion yen -- was hammered by a huge profit-padding scandal.
It was found that top executives had pressured underlings to cover up weak results for years after the 2008 global financial crisis.
The cash-strapped company has since sold off a number of assets, including its medical devices unit and most of its home appliance business, while it has also put its prized memory chip business on the block.