Toshiba Corp. anticipates that total losses at its nuclear business in the United States could be larger than earlier stated due to a write-down at its subsidiary Westinghouse Electric Co., a source familiar with the matter said Wednesday.

The development may further taint the financial standing of the company that has been battling to overcome a massive window-dressing scandal.

Toshiba is finalizing the size of an impairment loss at Westinghouse, which could reach tens of billions of yen, ahead of the release of its group earnings report for the April to December period in mid-February, the source said.

Last month Toshiba said it may need to write down the value of assets at CB&I Stone & Webster Inc., a nuclear plant builder Westinghouse obtained in 2015, possibly by several hundred billion yen.

Toshiba believes the devaluation of CB&I Stone & Webster may have seriously undermined the value of Westinghouse, the source said.

The source said Toshiba estimated the final write down in connection with U.S. nuclear plant operations may reach up to ¥500 billion as of the end of last year, but the total amount could change as the company combed through their financial data.

Toshiba has been focusing on nuclear energy operations as its core business but has been struggling to win orders for new power plants both at home and abroad, particularly after the 2011 Fukushima nuclear disaster.

The company booked an impairment loss of about ¥250 billion in its U.S. nuclear business in the last fiscal year through March 2016.