Tesla remains Musk’s best-known business, but its fortunes are less directly tied to the government than SpaceX, his rocket-building company.

The feud between Elon Musk and President Donald Trump heated up again Tuesday after the billionaire slammed Republicans over the president's spending bill.

The war of words between billionaire Elon Musk and President Donald Trump over the big bill of tax breaks and spending cuts is heating up again, with Musk claiming he may form a new political party and Trump blasting the Tesla CEO over electric vehicle subsidies.