Billionaire Trump supporter warns of 'economic nuclear winter' due to tariffs.

 A billionaire supporter of Donald Trump has urged the US president to pause his newly introduced trade tariffs, warning that failing to do so could lead to "a self-induced, economic nuclear winter."

In the midst of market turmoil, hedge fund manager Bill Ackman suggested that Trump take a three-month break to allow other countries to renegotiate their trade relationships with the US.

On Monday, another prominent Wall Street figure, JPMorgan Chase chairman Jamie Dimon, echoed Ackman’s concerns, saying Trump’s tariffs could lead to higher prices for American consumers.

Despite the backlash, President Trump has defended his new import taxes, stating that "sometimes you have to take medicine to fix something."

Trump argues the move will stimulate job growth and investment in the US, but economists warn that it could lead to rising costs for Americans and potentially trigger a trade war.

European and Asian stock markets continued to fall on Monday as they reacted to the global tariffs announced by Trump last week.

In a post on X on Sunday, Ackman acknowledged Trump’s argument that the global trade system had disadvantaged the US. However, he criticized the tariffs as "massive and disproportionate," pointing out that they didn’t differentiate between allies and adversaries.

Ackman, the billionaire founder of Pershing Square hedge fund, had previously supported Trump’s rival, the Democratic Party, but switched allegiance in July 2024, offering a significant endorsement from the business world.

Live updates as Trump's tariff turmoil continues:

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Trump unveiled a 10% "baseline" tariff on imports to the US last week, with higher rates up to 50% on goods from several key manufacturing centers, including countries in Asia. In response, multiple nations have pledged retaliation, with China already imposing new tariffs on US imports.

Ackman warned that Trump’s "economic war" against the world could severely damage investor confidence in the US.

He suggested that Trump take a 90-day "time out" to renegotiate unfair tariffs, potentially inducing trillions of dollars in new investment in the US.

Ackman’s Sunday post implied that it was now up to Trump to act after previously urging other world leaders to "pick up the phone" and negotiate with him.

As global stock markets continue to slide on Monday, Dimon shared his perspective in a letter to shareholders, cautioning that the tariffs "are likely to increase inflation and may increase the probability of a recession." He added that resolving the issue quickly would minimize the cumulative negative effects, which could be hard to reverse.

Trump’s officials have downplayed recession concerns, with the baseline 10% tariff now in effect. Higher tariffs on certain countries are scheduled to take effect Wednesday.

On a flight back to Washington DC on Sunday, Trump told reporters that European and Asian nations were "dying to make a deal."