One U.S. analyst said this week that Apple's demand for NAND could double next year and some estimate Apple already consumes about a third of global supply.
"If they can get a commitment from a key customer to build that fab, then it could be a fairly lucrative business, given the strong demand growth in smartphones," said Damian Thong, senior technology analyst at Macquarie Securities in Tokyo.
Sasaki said that the effect on NAND shipments of a brief cut in power to the company's Yokkaichi plant in central Japan on December 8 would not become clear until at least the new year. The outage forced it to halt operations at the plant until December 10.
Toshiba, the world's second largest supplier of NAND chips after South Korea's Samsung, had previously said shipments could fall by up to 20 percent in January and February.