The tech billionaire and key adviser to U.S. President-elect Donald Trump has taken to social media to air his grievances with the British government.

In the early hours of New Year’s Day, Elon Musk lobbed a series of angry posts and allegations towards British Prime Minister Keir Starmer – engulfing his government in a very public fight that it really doesn’t want.

For much of the period since Election Day, the billionaire has been staying at a $2,000-a-night cottage at Mar-a-Lago, giving him easy access to the president-elect.