The conglomerate agreed last year to sell the world's second-biggest producer of NAND flash memory chips to a consortium led by US private equity firm Bain Capital to plug a financial hole left by the bankruptcy of its US nuclear unit. It had faced a March 23 deadline to win Chinese antitrust approval to sell the business by March 31.

In a statement, Toshiba said it had yet to confirm regulatory approval from all authorities, without naming China.

"We do not yet know when the transfer will be completed, but we will continue to aim for the sale soon," Toshiba said. A spokesman said the company had not yet given up on closing the deal by the end of this month.