A Japanese investment fund has secured about 1 trillion yen ($6.8 billion) to buy out Toshiba Corp. and notified the embattled conglomerate that the amount was offered by a group of more than 10 Japanese companies, a source familiar with the matter said Monday.

But Japan Industrial Partners Inc. failed to meet Toshiba's request to submit a letter of loan commitments from major banks by Monday, the source said, leaving uncertain whether funds can be guaranteed for the takeover estimated at some 2.2 trillion yen in total.

Japan Industrial Partners, which leads a consortium that Toshiba designated the preferred bidder for the potential buyout, appears to be basing its total cost estimate on share price, as the figure equals the company's market capitalization, the source said.

In early October, Toshiba selected the consortium as the preferred bidder over Japan Investment Corp., a state-backed fund seeking to team up with Bain Capital for the buyout.

Toshiba has been struggling to recover from problems such as a window-dressing scandal and a massive loss in U.S. nuclear power business that surfaced in the 2010s.

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