White House Press Secretary Karoline Leavitt has urged investors to "trust" Donald Trump's "economic formula" after global and US markets tumbled in response to the president's sweeping new reciprocal tariffs.

In an interview on CNN Thursday, Leavitt was asked what her reaction was to "global markets tumbling" following Trump's announcement, which included tariffs of at least ten percent on nearly all US trading partners.

"To anyone on Wall Street this morning, I would say trust in President Trump. This is a president who is doubling down on his proven economic formula from his first term," she said.

"It's the rule for the Golden Age of America and the US is no longer going to be cheated by foreign nations...this is indeed a national emergency."

Donald Trump
Around 60 countries will be charged a tariff at half the rate they charge the US

The new policy will impose a baseline 10 percent tariff on all goods from all countries except those compliant with a free trade agreement between Mexico, Canada and the United States. Importers of goods from other countries will begin paying the baseline tariff at midnight on Saturday.

Around 60 countries will be charged a tariff at half the rate they charge the US. Those reciprocal tariffs will go into effect at midnight on April 9. Trump said the tariffs would punish other countries for years of unfair trade practices and bolster US manufacturing.

US stocks were severely rattled Thursday, amid fears the tariffs could threaten to plunge the country into a recession.

Futures for the S&P 500 slumped 3.4 percent in early trading on Thursday, putting it on track for its worst day since September 2022. The Dow Jones Industrial Average was down 1,200 points while the Nasdaq composite tumbled 3.8 percent.

Shares of Nike plunged 11 percent while and Apple's dropped 8 percent Thursday. Oil prices fell more than 4 percent and the US dollar hit its lowest level against the Japanese yen since early October.

In Europe at midday markets were also sharply lower. Germany’s DAX fell 2.4 percent, the CAC 40 in Paris lost 2.7 percent and Britain’s FTSE 100 fell 1.5 percent.

The White House has suggested the new tariffs would raise $600 billion a year. But economists warn the tariffs threaten to grind down growth for the US and other economies while worsening inflation.

The tariffs come after Trump last week announced 25 percent taxes on foreign-made cars. In recent weeks, the president has also imposed levies against China, Canada and Mexico; and expanded trade penalties on steel and aluminum.

Trump has also imposed tariffs on countries that import oil from Venezuela and he plans separate import taxes on pharmaceutical drugs, lumber, copper and computer chips.

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