Pro-mass immigration GOP megadonor billionaires the Koch brothers are now committed to working against President Trump’s two leading populist issues: immigration and trade.

In a statement to CNBC, the president of the Koch brothers-funded Americans for Prosperity announced that the Kochs’ network of organizations would be fighting against Trump’s proposed 25 percent tariff on imported steel and ten percent tariff on imported aluminum.

Tim Phillips, president of the Koch Brothers-backed Americans for Prosperity, noted that Trump narrowly won in Iowa and Wisconsin, two heavily rural states that could suffer if countries put in retaliatory tariffs on American agricultural goods.

It hurts the administration politically because trade wars, protectionism, they lead to higher prices for individual Americans,” Phillips said. “It’s basically a tax increase.”

Likewise, the Koch brothers have been ardent opponents of Trump’s popular pro-American immigration agenda, which has secured history-making wage growth for American workers in the construction industry, the garment industry, for workers employed at small businesses, and for black Americans.

Trump’s effort to reduce legal immigration, wildly popular with GOP voters and black Americans, is also opposed by the Koch brothers, who prefer the Washington, D.C.-imposed cheap labor economic model of importing more than one million legal immigrants a year to provide a never-ending flow of inexpensive workers to businesses while also keeping U.S. wages down.

“We just need to know there’s going to be no reduction to legal immigration,” president of the Koch-backed LIBRE Initiative, Daniel Garza, previously said.

The Koch brothers now join forces with House Speaker Paul Ryan and establishment consultants like Karl Rove who are advocating against Trump’s proposed protective tariffs, as Breitbart News reported.

At the core of the argument against Trump’s tariffs is the claim that American consumers will be hit with skyrocketing product prices.

Trade expert and White House adviser Peter Navarro, though, has debunked the claims coming from the free trade absolutism wing of the Republican Party, calling it a “bunch of horse-puckey,” in an interview with Breitbart News Saturday.

He said that the ten percent tariff on aluminum would only raise the cost of a six-pack of beer by about a cent-and-a-half and would only raise the construction cost of a $330 million 777 Dreamliner by about $25,000.

“There’s virtually no downstream effects, despite what the pundits might be saying on TV, and it’s all good for the aluminum industry,” he said.

“I think the record is clear on these free trade agreements. They always are done with promises for significant jobs for Americans and significant access to markets, and we always lose dramatically once the ink is signed,” he said.

Multinational free trade agreements have been responsible for massive manufacturing outsourcing and job loss over the last two decades. For example, the KORUS free trade agreement has displaced at least 60,000 American workers since its enactment in 2007, with more than 75,000 American jobs being eliminated from the deal.

Meanwhile, since the North American Free Trade Agreement (NAFTA) took effect in the 1990s, at least one million net U.S. jobs have been lost because of the free trade deal. Between 2000 and 2014, there have been about five million manufacturing jobs lost across the country as trade deficits continue soaring.

The Trans-Pacific Partnership (TPP) free trade agreement, which Trump ultimately killed, was supported by both the Democrat and Republican apparatus, but was expected to wipe out potentially one out of every four American jobs in the future had the agreement been signed.

TPP would have gutted American workers’ wages, with all workers having to undergo pay cuts except for the top ten percent of workers.

One former steel town in West Virginia lost 94 percent of its steel jobs because of NAFTA, with nearly 10,000 workers in the town being displaced from the steel industry. Since China entered the World Trade Organization (WTO) in 2001, there have been 3.2 million American jobs lost with 2.4 million of those jobs coming from the U.S. manufacturing sector.

John Binder is a reporter for Breitbart News. Follow him on Twitter at @JxhnBinder.