"When it comes to bankrupting our country with waste & graft, we live in a one-party system, not a democracy," Musk said in the announcement.

The tech billionaire formally declared the "America Party" after President Trump signed his signature bill, setting the stage for a dramatic political confrontation.

A public feud between President Donald Trump and his on-again, off-again ally, billionaire Elon Musk, reignited this week after an apparent truce lasted less than a month.