WASHINGTON : The United States is set to impose new tariffs that could hit dozens of countries soon, trade envoy Jamieson Greer signaled Tuesday, with President Donald Trump's temporary global levies due to expire this week.

The Trump administration has prepared fresh tariffs targeting 60 trading partners over their alleged failures to act against forced labor, as officials push to rebuild the US leader's trade agenda after legal setbacks.

"We expect to see some action soon," Greer told CNBC when asked if new duties were incoming. He did not specify a timeline.

Trump imposed a 10-percent global duty this year after a swath of his tariffs were struck down by the Supreme Court in February, but this levy expires on Friday.

Analysts expect that new tariffs over forced labor concerns -- set between 10 percent and 12.5 percent -- would replace these temporary duties.

They come as Trump makes a renewed push to use tariffs as leverage against US trading partners, sparking fears of retaliation and diplomatic tensions.

Washington announced a fresh 25-percent duty on certain Brazilian goods last week, and on Monday unveiled a 50-percent levy on many Canadian products to take effect in 30 days.

Canadian Prime Minister Mark Carney said Tuesday that he was looking at "all options," adding that he and Trump had agreed to "intensify discussions" in the coming weeks on a possible deal.

On Tuesday, Trump announced a new 100 percent sector-specific tariff on imported generic drugs to take effect from August 2028, with that level rising to 200 percent in 2029.

For now, the US leader said the tariff on generic drugs would be cut to zero from August 2026, in an effort to build a window for the onshoring of such pharmaceutical production to the United States.

- Forced labor concerns -

Greer said Tuesday that new action on forced labor will cover the majority of US trade, with the moves likely to reignite trade tensions.

A 10-percent tariff rate would hit US imports from partners including Canada, the European Union, Mexico, Taiwan and the United Kingdom. They were found to have taken steps against forced labor.

Goods from over 40 other major economies like China, India and Japan face a 12.5 percent levy.

The EU previously said that it considers tariffs imposed on these grounds "unjustified."

- Canada pressure -

Washington's planned 50-percent tariff on Canada also comes as US-Mexico talks over a North American free trade pact intensify.

Washington recently declined to extend the accord in its current form.

Greer is set to travel to Mexico from Wednesday to Friday for discussions linked to a joint review of the US-Mexico-Canada Agreement (USMCA).

But negotiations with Canada have proceeded at a slower pace. Carney on Tuesday did not suggest that he would head to Washington for talks.

Some lawyers see Trump's use of an untested legal provision -- Section 338 of the Tariff Act of 1930 -- as a means to gain leverage over Canada in USMCA negotiations.

Trade lawyer Dave Townsend of Dorsey & Whitney added that higher tariffs "appear to be aimed at encouraging an agreement between Canada and the United States, or in retaliation for the failure to reach such agreement, or both."

The question, he said, is whether both sides will start a "cycle of escalation and retaliation."

Crucially, Trump's latest salvo will not exempt affected Canadian products entering his country under the USMCA.

Trump told reporters Tuesday that the Canada tariffs were unrelated to his earlier threats over wildfire smoke that descended into the United States.

- Brazil tensions -

US plans for a 25-percent tariff on Brazilian goods over accusations of unfair trade practices have separately drawn a sharp rebuke from the Latin American giant.

The levy is due to take effect Wednesday, while shaping up as a major campaign flashpoint just months before Brazil's presidential election.

A range of products like beef, coffee and certain aircraft parts will be exempted, as will some goods that the United States does not produce.

Still, the American Chamber of Commerce for Brazil recently warned that Washington's measure places Brazil among countries "facing the most restrictive conditions for access to the US market," affecting more than $11 billion in exports.