Toshiba has revealed additional accounting irregularities after a multi-billion dollar accounting scandal last year, rekindling doubts over the company's pledge to improve transparency.

The laptops-to-nuclear conglomerate said it had overstated past profits by ¥5.8 billion (A$69 million) on a pretax basis due to seven new accounting errors, on top of the ¥224.8 billion in overstated profits it has already announced.
Toshiba said the company had treated the additional errors as losses in financial reports for two quarters through December, but had not publicly announced them because the amount was below the threshold requiring regulatory disclosure.
The company "lacked awareness for appropriate disclosure", a Toshiba spokeswoman said.
Fixing responsibilities for the latest errors, Toshiba said it had "punished" 40 more employees, in addition to 26 which it said previously had been punished. The company has not specified what form the punishment has taken.
Toshiba also said it would aim to bolster internal controls by hiring a permanent auditor who will oversee its accounts to ensure the company complies with regulations.
Toshiba "will make a united effort to improve internal control and corporate culture," it said in a statement.
The conglomerate also announced it will unveil this week unveil its strategy for the next fiscal year, which, analysts say, will include plans to boost its finances with the sale of business units.
In the wake of the book-keeping scandal in which Toshiba overstated profits from around 2009, CEO Masashi Muromachi has announced more than 10,000 job cuts and plans to sell its loss-making laptops and home appliances businesses.
Toshiba last week said it granted Canon exclusive negotiating rights to buy its medical equipment unit after a hotly contested auction, and one source with knowledge of the talks put Canon's offer at more than US$6 billion.
Funds from the deal will help Toshiba drop earlier plans to seek about US$1.8 billion in additional loans from Sumitomo Mitsui Banking Corp, Mizuho Bank and Sumitomo Mitsui Trust Bank, sources familiar with the situation said.
The deadline for finalising a deal is Friday.