The US government should impose further trade restrictions against Mexico to prevent the dumping of steel products into American markets, say the top executives of two of the biggest US steelmakers.

Nucor Corp. Chief Executive Officer Leon Topalian and Cleveland-Cliffs Inc. CEO Lourenco Goncalves used their quarterly earnings calls to say that recent moves by the Biden administration to impose new tariffs on steel diverted through Mexico don’t go far enough to protect the domestic industry.

The US is applying the tariffs to steel and aluminum shipments coming via Mexico in a bid to prevent China from circumnavigating existing levies through so-called transshipments. The measure, announced July 10, applies 25% tariffs to steel arriving from Mexico that wasn’t melted and poured in that country, the US or Canada.

“We think it’s the first first step that the administration put in place a few weeks ago with Mexico, but it’s not enough,” Topalian said. “You’re going to see Nucor continue to advocate vocally in Washington — regardless of the administration — to create a level playing field that protects this industry from illegally dumping subsidized steels from making out into the shores of the United States.”

Nucor’s CEO said he still has concerns about rebar and other steel products including electrical conduit that need to be brought into control. Meanwhile, Cliffs’ top executive accused Mexico of practicing “bad behavior” in steel markets by taking advantage of North American trade agreements.

“For too long, Mexico has enabled countries like China, Japan, South Korea, Brazil and several others to get away with dumping steel into our domestic markets using Mexico as a transshipment ground with zero or no value-added,” Goncalves said. “It’s great to see action being taken, but we need a lot more.”