Antitrust officials in China's Ministry of Commerce are concerned about the role SK Hynix Inc. will play in the sale of Toshiba Corp.'s memory chip business as the country commences a review of the deal, according to sources.

The officials are looking at the fact that Hynix could take a sizable stake in the business if the sale goes ahead, the sources, who asked to remain anonymous as they weren't authorized to speak on the matter, said.

From Toshiba's side, they may need to provide stronger assurance to regulators that it won't hurt competition.