Wall Street stocks tanked Friday after President Donald Trump vowed a tough response to new Chinese tariffs, escalating the trade war amid rising fears of recession.

At the closing bell, the Dow Jones Industrial Average was down more than 600 points, or 2.4 percent, at 25,630.52.

The broad-based S&P 500 fell 2.6 percent to 2,847.48, while the tech-rich Nasdaq Composite Index tumbled 3.0 percent to 7,751.77.

President Donald Trump declared Friday that he had "hereby ordered" American companies "to immediately start looking" for alternatives to operating in China, hours after Beijing announced new trade sanctions on U.S. products.

But as markets in the U.S., Asia and Europe tumbled, the White House offered no further details or explanation of Trump's intentions.

Instead, the president tweeted that he would be "responding to China's Tariffs this afternoon."

"This is a GREAT opportunity for the United States" he wrote.

The U.S. has said it plans to impose 10% tariffs on $300 billion of Chinese goods in two steps, on Sept. 1 and Dec. 15.

China responded Friday with new tariffs of 5% and 10% on $75 billion of U.S. products in retaliation, deepening a conflict over trade and technology that threatens to tip a weakening global economy into recession.

Like Trump's, the Chinese tariffs will be imposed in two batches — first on Sept. 1 and then on Dec. 15.

China will also go ahead with previously postponed import duties on U.S.-made autos and auto parts, the Finance Ministry announced.