Jan 4 (Reuters) - Foreign investors turned net sellers of Japanese equities in the week ended Dec. 25, 2020, on concerns over the spread of a mutant variant of the coronavirus, first detected in Britain.

Overseas investors were net sellers of stocks worth 176.47 billion Japanese yen ($1.71 billion) in the Dec. 21-25 week, marking their biggest weekly net selling in eight weeks, data from Japanese exchanges showed.

They sold 126.46 billion yen worth of derivatives and 50.01 billion yen in cash equities markets, the data showed.

The Topix index fell 0.8% in the week ended Dec. 25, while the Nikkei share average slipped 0.4%.

However, both the indexes recorded solid gains in 2020. The Topix index rose 4.8% last year, while the Nikkei average gained 16%. ($1 = 102.9900 yen)

(Reporting By Gaurav Dogra and Patturaja Murugaboopathy; Editing by Shailesh Kuber)