Peter Navarro, President Donald Trump's top trade adviser, on Monday dismissed tech-billionaire Elon Musk's push for "zero tariffs" between the United States and Europe, calling the Tesla CEO a "car assembler" reliant on parts from other countries.

CEO Elon Musk took to his social media site, X (formerly Twitter), to criticize President Donald Trump’s tariff policies — and Peter Navarro, the administration’s top trade adviser, who is widely believed to be their architect.

Trump trade adviser Peter Navarro sparred with CNBC’s “Squawk Box” hosts Monday on whether the administration’s reciprocal tariffs will actually lead to successful negotiations between the U.S. and foreign countries.