Financial markets reversed course on Friday after a three day rally, dropping as consumer confidence plummets amid the coronavirus pandemic.
The Dow Jones led US indexes lower, sliding more than 4%. European markets also declined.
The falls came despite US approval of a massive aid bill as the number of virus cases in the US surpassed China.
University of Michigan data also showed US consumer confidence dropped to its lowest level in three years in March.
"The outlook for the national economy for the year ahead weakened dramatically in March, with the majority now expecting bad times financially in the entire country," the director of the survey said in a statement.
More than 3 million Americans filed for unemployment benefits last week, a record high that follows widespread forced business, school and other closures as authorities try to limit the spread of the virus.
Concerns about the economic impact have prompted market gyrations and wiped trillions of dollars worth off of value off shares since February, but prices had recovered some ground this week as governments and central banks around the world moved forward with plans to blunt the economic impact of the pandemic.
On Friday, President Donald Trump was expected to sign a more than $2tn (£1.7tn) relief package, after the US Congress approved the aid for households and companies. It follows unprecedented steps by the Federal Reserve to shore up the economy.
The Dow and the S&P 500 on Thursday had marked their biggest three-day gains since the Great Depression in anticipation of the measure. They remained up about 10% for the week.
However, analysts have said they expect investors to remain on edge until the pandemic is under control.
The University of Michigan survey found consumer sentiment fell 11.9 points in March - the biggest one month drop since October 2008, at the height of the global financial crisis.
Wells Fargo analysts said the figures signalled another "body blow" to the economy.
"We are in the early stages of this crisis and are only now beginning to see its severity in the economic data," they wrote in a report.
The S&P 500 fell more than 3.3% and the Nasdaq dropped 3.8% on Friday. London's FTSE 100 tumbled more than 5%, while main indexes in France and Germany also fell. Earlier Asian markets had gained, with the Nikkei 225 up 3.8%.
Cruise companies, including Norwegian and Carnival, were among the biggest losers on US indexes. Boeing, which had seen share prices surge this week on expectations it would received, also dropped more than 6%, after officials rebutted the idea.