Here's a classic Washington versus Detroit showdown, with a twist of Beijing in the mix. On Tuesday, Transportation Secretary Sean Duffy took a swing at Ford Motor Co. (F), sending a letter to CEO Jim Farley that basically said, "Hey, maybe you should rethink your Chinese business partners."

According to a Reuters report, Duffy didn't mince words. He urged Farley to wind down Ford's battery and vehicle-related deals with a who's who of Chinese auto and battery giants: CATL, Geely Automobile Holdings (OTC: GELHY) (OTC: GELYF), and BYD Co. Ltd. (OTC: BYDDY) (OTC: BYDDF). The department, he wrote, has "profound concern" about these arrangements.

Duffy's letter zeroed in on Ford's plan to use licensed CATL technology at its Marshall, Michigan battery plant. That's a sore spot, given CATL's spot on a Pentagon list of companies allegedly linked to China's military. The Transportation Department, Duffy said, is "deeply alarmed" by Ford's dependence on such a partner.

He also took issue with Ford's timeline for moving production of the Lincoln Nautilus out of China. The current schedule, he argued, would keep Ford tied to Chinese manufacturing for years to come. That's a notable stance, especially since Commerce Secretary Howard Lutnick had previously praised the decision.

But Ford isn't just rolling over. The company fired back on Tuesday, calling Duffy's letter "a wrongheaded attempt to capture headlines." In a statement, Ford said, "While others continue to import Chinese batteries, Ford is investing to build batteries here in America," adding, "Ford owns the plant, controls the operation and employs the workforce."

Ford also cried foul on the facts. "Ford has not proposed a joint-venture framework as described in the letter," the automaker said. That's a direct rebuttal to reports from February, when Farley reportedly discussed forming joint ventures that could let Chinese automakers into the U.S. market.

So, what's really going on here? On one hand, you have a Trump administration that's clearly wary of any U.S. company getting too cozy with Chinese firms, especially in sectors like EVs and batteries that are seen as strategically important. On the other, you have Ford, which is trying to navigate a global supply chain while also making nice with the folks in Washington.

It's a tricky spot for Farley. He's already drawn a line in the sand on Chinese EVs, saying, "Should not let them into our country." But he's also got to keep Ford competitive, and that means making deals with whoever has the best technology and prices, even if they're based in Shenzhen.

Investors seem to be taking the spat in stride, at least for now. Ford shares were up 0.21% at $14.03 during pre-market trading on Wednesday. That's a pretty muted reaction, which suggests the market isn't expecting this to blow up into a full-blown crisis just yet.

But it's worth watching. If the administration starts applying real pressure, like blocking licenses or imposing tariffs, Ford could find itself in a bind. For now, though, it's a war of words, and both sides are digging in.