U.S. President Donald Trump holds notes about Tesla cars while being shown various models parked in front of the White House in Washington, D.C., March 11. Reuters-Yonhap

An adviser to U.S. President Donald Trump said Tuesday that a planned increase in a tariff on Canadian steel and aluminum imports to 50 percent will not take effect this week, a move that came after Ontario agreed to suspend a 25 percent surcharge on its electricity exports to the United States.

Peter Navarro, the White House adviser, made the remarks hours after Trump announced he had instructed Commerce Secretary Howard Lutnick to add an additional 25 percent tariff on steel and aluminum imports from Canada to bring the total tariff on the metals to 50 percent, starting Wednesday.

Ontario Premier Doug Ford suspended the surcharge after a conversation with Lutnick.

"That's correct," Navarro told CNBC when asked if the 50 percent tariff would not take effect Wednesday.

In the morning, Trump announced a plan to double the tariff on the Canadian metals to 50 percent as his administration is set to start imposing a 25 percent tariff on all steel and aluminum imports Wednesday, as part of his drive to use tariffs to pare down America's trade deficits and boost domestic manufacturing.

"Based on Ontario, Canada, placing a 25% Tariff on 'Electricity' coming into the United States, I have instructed my Secretary of Commerce to add an ADDITIONAL 25% Tariff, to 50%, on all STEEL and ALUMINUM COMING INTO THE UNITED STATES FROM CANADA, ONE OF THE HIGHEST TARIFFING NATIONS ANYWHERE IN THE WORLD," Trump wrote on Truth Social.

"This will go into effect TOMORROW MORNING, March 12th," he added.

Trump also demanded that Canada immediately drop its "anti-American farmer tariff of 250 percent to 390 percent" on various U.S. dairy products.

He warned if other "egregious, long-time" Canadian tariffs are not dropped, he will substantially increase tariffs on cars coming into the U.S. on April 2, which he said will "essentially, permanently shut down the automobile manufacturing business in Canada."

"Those cars can easily be made in the USA!" (Yonhap)