Elon Musk, the world's richest man according to Bloomberg's Billionaires Index, took aim at President Donald Trump's proposed spending package, calling it a "fiscal disaster."

Musk, the former head of the Department of Government Efficiency, left the role as the legislation moved through Congress.

"This spending bill contains the largest increase in the debt ceiling in US history! It is the Debt Slavery Bill. I think a bill can be big or it could be beautiful. I don't know if it could be both," Musk, No. 1 on Bloomberg's Billionaires Index, wrote on X on Wednesday.

The House approved the 1,100-page One Big Beautiful Bill Act on May 22, sending it to the Senate. The bill pairs $1.2 trillion in cuts to Medicaid and food assistance with permanent tax breaks and $150 billion in new defense and border security funding. The Congressional Budget Office estimates it will add $2.4 trillion to the deficit over the next decade, with some forecasts pointing higher.

The timing is striking: U.S. national debt is already nearing $37 trillion, a historic high that has amplified concerns among fiscal conservatives and tech leaders. The White House is pushing for Senate passage before July 4.