Alcoa Corp, the giant US aluminum manufacturer, has asked the US Commerce Department to exclude some of its Canadian aluminum imports from tariffs.

Alcoa said there are no US aluminum producers that can meet its specifications for rolling slabs used at the company's plant in Warrick, Indiana, to produce aluminum for can manufacturers.

Alcoa filed five requests asking for waivers from the administration's 10 percent tariff on imports of the lightweight metal.

Tariffs of 25 percent on steel imports and 10 percent on aluminum imports were imposed by the Trump administration on steel and aluminum imports from Canada, Mexico and the European Union in June as part of a crackdown on alleged trade abuses.

That prompted retaliatory moves as the EU imposed 25 percent tariffs on $3.3 billion worth of US imports starting June 22. Mexico imposed tariffs on pork bellies, apples, grapes, cheeses and flat steel. Canada also imposed tariffs on US steel, aluminum and other products.

"During a time of record demand for aluminum in the United States, it is critical that companies have access to a steady source of supply. That's why we continue to call for quota-free tariff exemptions for countries like Canada that play by the rules and operate as market economies," Matt Meenan, spokesman for The Aluminum Association, wrote in an email.

Alcoa said in July it would incur as much as $14 million a month in extra expenses, mainly from tariffs levied on aluminum imported from Canada, the company's primary supplier.

"Even if all the curtailed smelting capacity was back online and producing metal, the United States would still need to import the majority of its aluminum, and most of it from Canada. We believe that the Section 232 tariffs should be removed from Canada and other fair-trading partners," said Tim Reyes, president of Alcoa Aluminum, one of the company's three business units, according to Reuters.

In addition to Canada, the EU and Mexico, the US and China are also engaged in a trade dispute as both countries have slapped tariffs on each other's exports and are threatening to extend them to other products.