European stocks dropped Thursday, posting their sixth loss in seven sessions, with investors gripped by concerns about slowing economic growth ahead of next week's U.K. vote on whether to leave the European Union.

European equities were rattled Thursday after the U.S. Federal Reserve trimmed its 2016 forecast for growth in the world's largest economy to 2% from 2.2%, and as the central bank indicated it would take an even slower approach to raising interest rates.

Fed Chairwoman Janet Yellen said the U.K.'s June 23 referendum on whether the country will stay in the EU was a factor in its decision to leave interest rates steady. Two fresh opinion polls released Thursday added to recent surveys showing the British public is leaning toward supporting a so-called Brexit.

The Bank of England, as expected, on Thursday left its benchmark interest rate at 0.5%.

The Swiss National Bank said those lenders will need about 10 billion Swiss francs ($10.42 billion) in new capital to meet Switzerland's new capital requirements. The SNB made the statement in its 2016 financial stability report Thursday.

U.S. stocks erased early losses to close modestly higher on Thursday, ending a five-day streak of losses.

For the past several sessions, a British referendum scheduled for June 23 to decide whether the U.K. will remain in the European Union had been weighing on risky assets like equities.

On Thursday, stocks seemed to find some support after both sides in the referendum debate suspended campaigning for the day after British lawmaker Jo Cox died following a shooting attack. The British pound bounced on speculation the development could bolster the "remain" campaign.

But analysts played down the impact on U.S. stocks, noting the modest rebound came as equities ended a five-day losing streak. The bounce marks "a temporary respite in what is otherwise a risk-off day," said Art Hogan, chief market strategist at Wunderlich Securities.

Asian shares rose on Friday, but were set for weekly losses as investors favored safe haven assets due to fears that Britain will vote to quit the European Union, though the killing of a pro-EU lawmaker was seen swaying sentiment toward the "Remain" camp.

Campaigning for Thursday's referendum, which overshadowed this week's U.S. and Japanese central bank meetings, was temporarily halted after a British member of parliament, Jo Cox, was shot and fatally wounded on Thursday.

Japan's Nikkei stock index .N225 gained 1.6 percent, taking back some of its steep losses. But Japanese shares were still poised to shed 5.5 percent in a week in which the safe-haven yen soared after the Bank of Japan decided against delivering additional stimulus to counter waning inflation and weak global growth.

Japanese Finance Minister Taro Aso said on Friday that he was deeply concerned about "one-sided, rapid and speculative moves" seen in the currency market and would respond if necessary to ensure stability in currencies.