European stock index futures fell more than 2% on Friday, as a newly identified and possibly vaccine-resistant coronavirus variant drove investors out of riskier assets amid fears of a fresh hit to the global economy.
Futures tracking Europe's top 50 companies fell 2.3%, with 40,427 contracts exchanging hands by 0645 GMT. UK's FTSE futures dropped 2% while German DAX futures lost 1.9%.
Little is known of the variant detected in South Africa, Botswana and Hong Kong, but scientists said it has an unusual combination of mutations and may be able to evade immune responses or make it more transmissible.
Cyclical-heavy European stock markets have already been under stress this week as a resurgence in COVID-19 cases prompted new restrictions in several countries, while bets of faster US monetary policy tightening added to the nerves.
Travel stocks will be in focus when markets open for trading after Britain announced a temporary ban on flights from South Africa and several neighbouring countries from 1200 GMT on Friday.
Oil and metal prices lost ground as reports of the new virus variant fuelled economic slowdown worries.
New York's S&P 500 futures dropped 1.2%, with trading likely thinned by the US Thanksgiving holiday on Thursday and a shortened trading session on Friday.