LONDON, United Kingdom - Sports Direct, Britain's biggest sporting retailer, is planning to close up to a third of its loss-making USC fashion stores, an industry source told Reuters on Thursday.

The group, majority owned by founder and Newcastle United soccer club owner Mike Ashley, has filed a notice of intention to appoint receivers to USC, which is made up of 90 UK stores selling jeans, shoes and jackets to teens and twentysomethings.

Around a third of those shops will close with the rest continuing to trade, an industry source, who did not wish to be named, said on Thursday. A formal notice of intention usually gives a company 10 days before it has to declare insolvency.

Sports Direct declined to comment.

Sports Direct, which has over 430 UK sports stores and another 270 elsewhere in Europe, has owned USC since 2011 and it makes up the majority of the company's additional premium lifestyle, or fashion division.

The division, which has already undergone restructuring and store closures following the acquisition of fashion retailer Republic in 2013, posted losses of 7.8 million pounds for the 26 weeks to Oct. 26 in December.