On Tuesday, global stocks fell and safe-haven assets such as Japan's yen advanced as US-China tensions spiked over Nancy Pelosi's planned visit to Taiwan.
The S&P 500 futures were down 0.8%, with the other two stock market indexes also in negative territory. The European stock market fell.
China's CSI 300 index fell 2% while Taiwan's benchmark stock index also fell.
Tensions between the US and China have risen in recent days as speculation has grown that the Speaker of the US House of Representatives will visit Taiwan as part of a tour of Asia.
Pelosi is expected to visit Taiwan's president later in the day, according to reports.
If a senior US politician visits Taiwan, China will not sit idly by.
Chinese fighter jets flew to the edge of themedian line between Taiwan and the Chinese mainland as reports confirmed Pelosi's visit.
The worsening of relations between the world's two most powerful economies sent investors towards safe-haven assets.
The Japanese currency rose to a two-month high against the dollar. As investors sought the safety of government bonds, the yield on the 10-year Treasury note fell.
The threat of economic retaliation from China was worrying according to an economist.
He said that the economic response would be within the possibilities. The effects of trade sanctions could be worse.