TOKYO (Reuters) - Toshiba Corp 6502.T filed twice-delayed business results on Tuesday without an endorsement from its auditor and warned its very survival was in doubt, deepening a prolonged crisis at the Japanese conglomerate.

“There are material events and conditions that raise substantial doubt about the company’s ability to continue as a going concern,” Toshiba said in announcing bigger than previously estimated losses for the nine months through December.

The filing carried a disclaimer from auditor PricewaterhouseCoopers (PwC) Aarata LLC that it was unable to form an opinion of the results, increasing the likelihood that shares in the nuclear-to-TVs company will be delisted from the Tokyo Stock Exchange (TSE).

The move is a first for a major Tokyo-based firm, and puts the stock exchange center-stage as it weighs the pros and cons of forcing Toshiba to delist.

Toshiba Chief Executive Satoshi Tsunakawa expressed regret that the auditor could not form an opinion, and said Toshiba pressed ahead with submitting its results rather than seek an unprecedented third delay.

“The decision on any delisting is for the stock exchange to make,” he told a news conference in Tokyo, the latest in a string of briefings that have opened with apologies to shareholders. “We will do our utmost to avoid it.”

Failing to act tough with Toshiba would bring into question authorities’ credibility in maintaining standards for investors, but a delisting would complicate the crisis at Toshiba, increasing its financing costs and exposing it to further lawsuits from angry shareholders.

Slideshow ( 4 images )

Accountants have been questioning the numbers at U.S. nuclear subsidiary Westinghouse Electric Co, where massive cost overruns at four nuclear reactors under construction in the Southeastern United States have forced its Japanese parent to estimate a $9 billion annual net loss and take drastic measures.

PwC is questioning not only recent results, but also probing the books at Westinghouse for the business year through March 2016, sources have said, declining to be identified as they were not authorized to speak on the matter publicly.

The decision on whether or not to delist Toshiba now rests with the TSE. Toshiba has been on its supervision list since mid-March after failing to clear up concerns about its internal controls a year and a half after a 2015 accounting scandal.

There are no set rules governing how long the bourse should take to come to a conclusion.

Toshiba has put up its prized memory chip unit and other assets for sale, and Westinghouse has filed for Chapter 11 protection from creditors.

Toshiba also said on Tuesday it was considering an initial public offering or sale of smart meter group Landis+Gyr. Reuters last month reported that Toshiba was preparing a potential $2 billion divestment of the Swiss-based business.

Slideshow ( 4 images )

FOXCONN CHIPS BID?

Separately, Taiwan’s Foxconn has offered up to 3 trillion yen ($27 billion) for Toshiba’s chip business, nearly $10 billion higher than Toshiba’s own estimate, the Wall Street Journal reported, citing people familiar with the matter.

Such a proposal by Foxconn would also put Japanese regulators in a tough position as they have vowed to vet bidders to block a sale to investors it deems a risk to national security. Foxconn is considered such a risk because of its close ties to China.

Japan’s trade minister Hiroshige Seko repeated on Tuesday that Toshiba’s chip technology was important, not only for Japan’s growth strategy, but also in terms of jobs and information security.

“For those reasons, we continue to carefully monitor Toshiba’s business conditions and the sale of its chip business,” he said.

Toshiba declined to comment on its chips business. Foxconn, formally known as Hon Hai Precision Industry 2317.TW, also declined to comment.