President Trump lashed out at Apple on Friday, threatening the company with a 25% tariff on iPhones unless it moves production to the U.S.

“I have long ago informed Tim Cook of Apple that I expect their iPhone’s [sic] that will be sold in the United States of America will be manufactured and built in the United States, not India, or anyplace else,” Trump wrote on Truth Social. “If that is not the case, a Tariff of at least 25% must be paid by Apple to the U.S. Thank you for your attention to this matter!”

Trump’s post comes days after Apple’s major manufacturing partner, Foxconn, announced a $1.5 billion investment in its India unit. Apple has been looking to shift hardware production to India as the trade war with China under President Trump takes unpredictable twists and turns.

In an earnings call earlier this month, Cook said that the majority of iPhones sold in the U.S. “will have India as their country of origin.”

President Trump expressed his displeasure over Apple’s shift to India last week while he was in the Middle East, according to CNN. The two men also met on Tuesday, the outlet reported, although details on what they discussed were slim.

Trump has started ratcheting up attacks on companies trying to avoid the ramifications of U.S.-imposed tariffs. Just this weekend, he wrote a post calling for Walmart to “EAT THE TARIFFS,” rather than pass them on to shoppers.