Wall Street plunged in a broad sell-off on Friday as China and the United States traded their latest salvos in a prolonged trade war, spooking investors and erasing slight gains following a generally positive speech by U.S. Federal Reserve chair Jerome Powell.

The Federal Reserve will "act as appropriate" to keep the U.S. economy healthy, Fed Chair Jerome Powell said on Friday, remarks that did not say how fast it might cut interest rates, drawing fire from President Donald Trump.

U.S. President Donald Trump on Friday said he has ordered American companies to exit China after Beijing unveiled retaliatory tariffs on $75 billion in U.S. goods, throwing a new twist into the bitter trade war between the world's two largest economies.

The U.S. National Retail Federation (NRF) said on Friday it is "unrealistic" for American retailers to move out of China, the world's second-largest economy, as 95% of the world's consumers live outside the United States.

President Donald Trump said on Friday he was ordering U.S. companies to look at ways to close their operations in China and make more of their products in the United States instead, sending U.S. markets down sharply in a new rhetorical strike at Beijing as trade tensions mounted.

China said on Friday it will impose retaliatory tariffs against about $75 billion worth of U.S. goods, putting as much as an extra 10% on top of existing rates in the dispute between the world's top two economies.

Oil prices fell more than 2% on Friday after China unveiled retaliatory tariffs against about $75 billion worth of U.S. goods, marking another escalation of a protracted trade dispute between the world's two largest economies.

India is rolling back recent tax hikes on foreign and domestic equity investors and is accelerating a capital infusion of $10 billion into state-run banks, the finance minister said late on Friday, in an attempt to boost market sentiment and revive the slowing economy.

The Indian government announced measures on Friday to revive economic growth and markets including the withdrawal of higher taxes for foreign portfolio investors (FPIs) and said it would release funds for bank recapitalization upfront.

China on Friday threatened to impose tariffs on U.S. crude oil imports for the first time, sending prices down nearly 4% to two-week lows as the escalating bilateral trade war fed worries over a slowdown in global oil demand.