The copper levy would come after a probe into imports of the metal, broadening a slate of sector-specific tariffs Trump has imposed since returning to the White House.

"Today we're doing copper," he told a cabinet meeting Tuesday. "I believe the tariff on copper, we're going to make it 50 percent."

Commerce Secretary Howard Lutnick told CNBC shortly afterward that the rate will likely be implemented at the end of July or on August 1.

Trump also said Washington would soon make an announcement on pharmaceuticals, but officials would allow manufacturers time to relocate their operations into the country.

"We're going to give people about a year, a year and a half to come in, and after that, they're going to be tariffed," he said. "They're going to be tariffed at a very, very high rate, like 200 percent."

Apart from copper and pharmaceuticals, Trump has ordered probes into imports of lumber, semiconductors and critical minerals that could lead to further levies.

Lutnick told CNBC that US studies on pharmaceuticals and semiconductors would be completed by the end of the month, with Trump to set policies thereafter.

Beyond tariffs impacting sectors, Trump separately slapped a sweeping 10 percent tariff on goods from almost all trading partners in April.

These would have swiftly risen to steeper levels for dozens of economies including the European Union and Japan, but Trump paused their implementation until July 9.

The president this week again delayed their reimposition, pushing it to August 1 while insisting there would be no further delay.

- 'No extensions' -

"No extensions will be granted," Trump posted on Truth Social. "There will be no change."

The clarification came after Trump told reporters Monday night that the August 1 deadline was "firm, but not 100 percent firm."

In a push for further trade deals, Trump also sent letters to more than a dozen partners on Monday, including key US allies Japan and South Korea.

Products from both countries would be hit with 25 percent duties, Trump wrote in near-identical documents to leaders in Tokyo and Seoul.

Indonesia, Bangladesh, Thailand, South Africa and Malaysia were among other countries facing duties between 25 percent and 40 percent.

Most countries receiving the letters so far saw US tariffs at similar or unchanged rates from those threatened in April, although some like Laos and Cambodia received notably lower levels.

In his messages to foreign leaders, Trump warned of further escalation if there was retaliation against his levies.

Lutnick said 15 to 20 more letters could go out in the next two days.

- 'Two days off' -

Trump insisted Tuesday that "big money will start coming in on August 1."

US Treasury Secretary Scott Bessent added at the cabinet meeting that tariff income could exceed $300 billion by year-end.

The Trump administration is under pressure to show results after promising a flurry of deals following its tariff threats.

Trump said Washington was "probably two days off" from sending the EU a letter setting out an updated tariff rate for the bloc.

"They're very tough, but now they're being very nice to us," he said. "We are talking to them."

So far Washington has only struck two pacts, with Britain and Vietnam, besides an agreement to dial back staggeringly high tit-for-tat levies with China.

Lutnick said he expects to start a "bigger trade conversation" between Washington and Beijing in early August, alongside Bessent and US trade envoy Jamieson Greer.

And US talks with Britain are ongoing over steel and aluminum.

Trump recently doubled US tariffs on imports of both metals to 50 percent while exempting the UK from this increase. But Washington could double the levy on UK steel and aluminum too starting Wednesday, if it determined that London had not complied with the terms of their deal.

In threatening tariff hikes on various countries, Trump cited in his letters a lack of reciprocity in trading ties.