Mexico’s plans to retaliate against the Trump administration for its decision last week to impose tariffs on steel and aluminum imports started to come into focus Tuesday.

Meanwhile, American Petroleum Institute (API) CEO Jack Gerard said the tariffs would hurt the U.S. energy market, and three nonprofit advocacy groups funded in part by the Koch brothers urged Trump to rescind the new tariffs.

Last week, the European Union, Canada and Mexico each took retaliatory steps against the United States after the Trump administration imposed a 25% tariff on steel imports and a 10% tariff on aluminum imports. Both Brussels and Mexico City have since filed complaints with the World Trade Organization over the tariffs.

A decree from Mexico’s Ministry of the Interior with Tuesday’s date shows Mexico City plans to levy tariffs on American-sourced pork legs and shoulders, cheese, apples, potatoes, cranberries and bourbon whiskey, among other things.

‘Not Good For Us’

In an interview Wednesday on Fox Business Network, Gerard said API’s members were concerned that the Trump administration hasn’t “looked at energy in its true context,” and that the tariffs would be problematic for domestic oil and gas producers.

“We understand what the president is trying to do in terms of the broader discussions,” Gerard said. “But fundamentally, from an energy perspective, under [the North American Free Trade Agreement] we’ve had open border trade policy for many years. We’re significantly net exporters to Mexico.”

Gerard said many Americans don’t know that the United States imports “a fair amount of Mexican crude” to refineries along the Gulf Coast. Refined products and gasoline are then exported back to Mexico.

“We’re very concerned that what we’ve now entered into could disrupt the equilibrium, the balance we’ve achieved in energy trade. We would hope they would think clearly and specifically about energy and what this means for energy as the president is trying to accomplish his broader purposes.”

Gerard added that the tariffs would “create a great deal of uncertainty” for the oil and gas industry. “That’s not good for us, because then we tend to get conservative in our investments in creating American jobs and creating American energy,” he said.

Koch-Funded Groups Urge Rescission

On Tuesday, three conservative groups funded by leading Republican backers and oil and gas producers, the Kochs, — Freedom Partners, Americans for Prosperity and the Libre Initiative — penned a letter to Trump, urging him to “rescind all tariffs on steel and aluminum among our nation’s trading partners.” They called for the president to use this week’s G7 summit at La Malbaie, Quebec, as the venue to rescind the tariffs.

“These tariffs are already having the opposite effect of the 2017 tax cuts, raising prices on consumers and businesses that buy imported goods for consumption or use in production,” executives with the three groups said. “These moves have already hurt American businesses and caused great and unnecessary uncertainty and the pain will likely trickle down to American workers.”

According to reports, Trump had a combative phone call with Canadian Prime Minister Justin Trudeau on May 25, before the tariffs were announced. Trudeau was reportedly incredulous that Trump would impose the tariffs on Canada on national security grounds, to which Trump quipped “Didn’t you guys burn down the White House?” in reference to the War of 1812.

British troops, not Canadian forces, marched on Washington, DC, in 1814 and set fire to the White House. The attack was in retaliation for American forces attacking and burning the city of York, now Toronto, one year earlier. During the War of 1812, Canada was a collection of British colonies known collectively as British North America.