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Major players in the US copper industry have called on President Donald Trump to restrict exports of ore and scrap metal rather than imposing tariffs on imports, in his efforts to boost domestic production.

Trump’s executive order in February ordering an investigation into possible copper tariffs has upended the global market, driving US prices to a huge premium to international benchmarks and spurring a global race to get copper into the country before any potential tariffs are imposed.

The order called on the secretary of commerce to make recommendations on actions “including potential tariffs, export controls, or incentives to increase domestic production.”

In public comments in response to the US government’s section 232 investigation on copper, leading companies including miner Rio Tinto Group, fabricator Southwire Co. and trader Trafigura Group suggested that the administration should instead impose restrictions on exports of copper rather than tariffs on imports.

“The Trump administration should consider implementing export restrictions on domestically produced copper concentrate and copper scrap,” wrote Rio Tinto.

Southwire, which is the US’s largest manufacturer of copper wire, said: “The administration should focus on regulatory reform and restrictions on US copper exports as the primary tools to grow the US industry.”

Significant Importer

The US is the world’s largest exporter of copper scrap and also an exporter of copper ore, known as concentrates. However, a lack of sufficient domestic processing capacity means it is also a significant importer of refined copper metal.

Any serious curbs on US scrap supplies would redraw the market for scrap, which accounts for almost a third of copper supply. US shipments of waste copper were about 600,000 tons last year, according to research from Citigroup Inc. — an amount equivalent to some of the world’s largest copper mines. More than half of that goes directly to China for processing.

While several responses called for the US to impose restrictions on exports of copper scrap, and in some cases copper concentrates, many urged the administration not to place import tariffs on copper metal.