Billionaire investor Bill Ackman pleads with Trump White House not to declare a 'global economic war against the whole world at once'

Bill Ackman attends Legion of Honour Award Ceremony and Dinner at the Park Avenue Armory in New York City. (Credit: Sylvain Gaboury—Patrick McMullan via Getty Images)

• The Pershing Square hedge fund manager urged the Trump administration to freeze tariff plans for 90 days to give room for trade negotiations. The alternative would be a "self-induced, economic nuclear winter" and damage to trading relationships that could last for decades, he warned.

President Trump’s punitive tariffs—scheduled to take effect from Wednesday—risk mutually assured destruction to the global economy unless cooler heads prevail, according to Bill Ackman.