S equity markets.

That was off the back of concern around the retail trading frenzy that's gripped Wall Street this week.

The benchmark Stock 600 Index dropped 1.6% in morning trade on was on course to end the week, with its worst declined since late October.

Germany's DAX also declined.

The U.

S stock market had already been looking overvalued after a stimulus led rally last year, but it's being jolted this week by steep gains in heavily shorted stocks, including Gamestop on AMC Entertainment shares.

A video game retailer Gamestop on headphone maker Cost Corp doubled in early premarket trading.

On Friday, amateur traders returned a day after online brokerage APS, including Robin Hood, imposed buying restrictions on the stocks.

Fears also remained for traders around the potential economic damage from a new strain of the virus in Europe.

It's been a busy week for earnings to on.

On Friday, Sweden's Ericsson jumped 7% after reporting fourth quarter core earnings ahead of market estimates.

It's benefited from strong sales of five G equipment.

Bitcoin jumped as much as 14% to a two week high that after Tesler chief Elon Musk tagged the crypto currency in his Twitter biography.