Apple and Amazon.com will join Foxconn's bid for Toshiba 's semiconductor business, the Nikkei business daily quoted Foxconn Chairman Terry Gou as saying on Monday.

The two U.S. technology giants plan to "chip in funds", Gou said, according the newspaper. It was not clear if this would take the form of a direct investment in the semiconductor unit or would be financing for the deal.

Taiwan's Foxconn, formally known as Hon Hai Precision Industry Co Ltd, has also partnered with its Japanese unit Sharp in its bid.

Toshiba has valued its mamory chip business at least $18 billion, due to its deep ties with China. The company is depending on the sale of the unit to cover billions of dollars in cost overruns at its now bankrupt U.S. nuclear unit Westinghouse.

Toshiba will narrow down the field of interested parties for its memory business to one candidate by mid-June, and will seek to close a definitive agreement by the date of its annual ordinary general meeting of shareholders, scheduled for June 28. The company's ultimate objective is to close the transaction within FY 2017, to March 31, 2018.