The IPO is one of the various contingency plans being looked at by Toshiba's top executives, and some analysts and Toshiba shareholders favour it over the existing deal.

Toshiba agreed last September to sell Toshiba Memory, the world's second-biggest producer of NAND chips, to a consortium led by Bain Capital to cover billions of dollars in liabilities arising from now-bankrupt US nuclear power unit Westinghouse.

But the Japanese conglomerate no longer faces the pressure it once did to complete a sale, after raising $5.4 billion with a new share issue to overseas funds late last year, which with tax write-offs gives it sufficient funds to cover its liabilities.

Hong Kong-based activist investor, Argyle Street Management, a hedge fund with $1.2 billion under management, has voiced opposition to the sale, saying it was no longer necessary.

A Toshiba spokeswoman said there had been no change to the fact that the company was working towards completing the sale of the chip unit.