Ken Griffin, CEO of multi-strategy hedge fund major Citadel, has publicly criticised the Trump administration’s latest tax legislation, warning it would significantly worsen the US national debt, which already stands at $36tn, according to a report by the New York Post.

Speaking at Forbes’ Iconoclast summit in New York, Griffin described the so-called “Big, Beautiful” tax bill as fiscally irresponsible, highlighting that it risks adding “several trillion dollars” to the country’s debt burden. He questioned the logic of extending tax cuts amid a sizeable fiscal deficit and stressed that running deficits of 6-7% at full employment was unsustainable.

Griffin also raised alarm about the US’s growing financial risk in bond markets, suggesting that default risk pricing for the US is comparable to countries like Italy or Greece. He criticised the administration’s failure to rein in spending and warned of broader economic uncertainty due to trade policies and tariffs.

Taking aim at President Trump’s recent public criticism of Walmart’s CEO Doug McMillon over price hikes linked to import costs, Griffin defended corporate leaders for their transparency and rebuked the White House’s stance.

Although a Trump supporter in the 2024 election, Griffin has become a vocal opponent of the administration’s tariff and trade policies, arguing they undermine American economic competitiveness and consumer interests.

The White House has yet to respond to Griffin's remarks.