Toshiba has added to investor woes after the Japanese giant missed another deadline for filing results.
Toshiba said in a statement it needed more time as it was investigating “alleged occurrence of inappropriate pressures by certain senior managers” surrounding the purchase of CB&I Stone & Webster, a nuclear construction company, by its Westinghouse Electric subsidiary.
The alleged pressures may have been exerted over the value of the business since the acquisition.
The company said it had not so far found any irregularities that would affect the statement, but said it would need another month for lawyers to complete its results report.
The new deadline, if approved, would be 11 April. If it does not receive regulatory approval the company would be forced to report by 27 March or delist from the Tokyo Stock Exchange.
Toshiba had received approval to delay filing its third-quarter results for a month on 14 February, but announced it had missed the new 14 March deadline as well.
Investors had been waiting for the company to report a writedown of as much as £5bn on the nuclear operations, but the company demurred, saying its results were not ready.
Westinghouse has since hired bankruptcy lawyers to explore the possibility of closing the troubled business.
Another option to protect the main business could be a sale of the company's successful memory chip business.
Toshiba's chairman Shigenori Shiga resigned in February when the company missed its first deadline. Shares have almost halved in value since peaking in December.
Loizos Heracleous, professor of strategy at Warwick Business School, said: "The current problems stem from debatable strategic capabilities. Overly complex corporate portfolios, particularly if synergies across businesses are hard to detect, such as Toshiba’s diversified stable of businesses, are unlikely to deliver high returns.
"It is likely that banks will offer a lifeline to Toshiba. If that fails, the state may step in. What should happen next, is a hard-nosed evaluation and decisive management of the portfolio of Toshiba’s businesses."