Brazilian steelmakers’ trade group Labr on Monday said the United States is pressuring Brazil to reduce its exports of unfinished steel, part of a long fight between both countries.

“They have threatened us,” Labr President Marco Polo said of the United States. “If we don’t agree to tariffs they will lower our quotas,” he told reporters.

Brazil and the United States were engaged in a trade spat last year when U.S. President Donald Trump said he would impose tariffs on Brazilian steel and aluminum in a bid to protect local producers.

Washington has been seeking to reduce the quota for Brazilian steel exports since at least 2018, Reuters has previously reported.

Under the quota system, Brazilian steelmakers represented by Labr, such as Gerdau, Usiminas, and the Brazilian operation of ArcelorMittal, can export up to 3.5 million tonnes of unfinished steel a year, to be finished by U.S. producers.