A key Republican senator sees positive signs in the Trump administration’s trade discussions with Canada and Mexico, but he still has plenty of criticism for the White House, too.

In a major trade policy speech at the Heritage Foundation on Tuesday morning, Sen. Rob Portman is planning to focus on the effects of the Trump trade agenda on the auto industry, a key business in his manufacturing-heavy home state of Ohio.

“I’m still reviewing the details of the updated NAFTA agreement, now called the United States-Mexico-Canada Agreement, but I am encouraged by what I’ve seen so far,” Portman, a former U.S. trade representative, is expected to say. “One of the most substantial changes to NAFTA is the rules of origin for automobiles. In the time since NAFTA was ratified 24 years ago, the United States has lost about 350,000 auto jobs, while Mexico gained 430,000.”

Portman’s indications of support of that framework is in contrast with his view of what the Commerce Department has done with using Section 232 of the Trade Expansion Act to impose tariffs, even on close allies, using a nebulous “national security” justification.

In his remarks, Portman is expected to speak to the proposal, which has been stalled in the Senate, to rework the trade law to restrict it to true national security implications.

“The administration has used Section 232 to impose a new 25 percent tariff on steel and 10 percent tariff on aluminum imports worldwide,” the Ohio senator is expected to say. “For certain countries and certain products, I believe there is a national security issue with steel — including electrical steel, which is critical to the grid. But broadly imposing tariffs on our allies risks them retaliating by putting tariffs on our products.”

“Simply put, auto and auto part imports are not a national security threat, and as I’ve been saying for months, these tariffs are a bad idea,” reads a copy of Portman’s prepared speech, which was obtained by Roll Call.

Portman will outline views more favorable to Trump and the harder line of his administration when it comes to trade with China, citing Chinese policies such as requirements for joint ventures for U.S. automakers to do business in the communist country.

The speech is expected to include a degree of support for the tariff announcements as part of negotiations with China.

“While I do have concerns about some of the collateral damage these tariffs can do to folks trying to make products in America, I think this assertiveness on China is needed,” Portman is scheduled to say. “Republican and Democrat administrations alike have tried to get China’s attention on the trade issue and failed. China has been violating and circumventing our trade laws for decades. I think the Trump administration now has China’s attention, and I applaud the president for taking a tough stand.”

But Portman is also expected to say that he does not view shortcuts like the purchase of additional soybeans from American producers by China as a solution to the trade issues between the two countries.

“Instead, the United States should push for structural changes to the Chinese economy to reduce the ways Beijing distorts the economy in its favor and tilts the playing field away from American workers,” Portman is scheduled to tell the Heritage audience.

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