"The tariffs, you know they're all set, they go into effect tomorrow," he said.
U.S. stocks closed sharply lower after President Donald Trump confirmed that tariffs against major trading partners Mexico and Canada will go into effect starting next day.
"There's no time left for either Mexico or Canada," Trump said at the White House when a reporter asked if the levies would take effect from Tuesday.
"The tariffs, you know they're all set, they go into effect tomorrow," he said.
The Dow Jones industrial average fell 1.5 percent to 43,191.24 points, while the broader S&P index lost 1.8 percent to finish at 5,849.72 points.
The tech-rich Nasdaq suffered a more severe slump, closing down 2.6 percent at 18,350.19 points, while the CBOE volatility index, or VIX - known as Wall Street's "fear gauge" - rose, reaching its highest level since December.
But despite the uncertainty, "the backdrop remains favorable," Edward Jones' Angelo Kurkafas told AFP.
He added that the trade was in line with the volatility seen over the past three months" in financial markets.
Among individual stocks, chip titan Nvidia tumbled 8.7 percent after Singapore authorities said they were probing whether servers containing its chips that ended up in Malaysia may have violated US laws against selling chips in China.
According to Home Secretary K. Shanmugam, the servers were supplied to Singapore-based companies by US firms Dell and Super Micro Computer.
Super Micro closed down 13.0%, while Dell shares fell 7.0%. | BGNES