The U.S. national debt has surged past $40 trillion for the first time, more than doubling in less than a decade as Washington's mounting fiscal burden reaches another historic milestone, Treasury Department data showed.

Total public debt outstanding reached $40.047 trillion on Tuesday, rising from $39.987 trillion a day earlier, the Treasury’s Debt to the Penny dataset showed.

The total comprises $32.266 trillion in debt held by the public and $7.782 trillion in intragovernmental holdings.

The federal debt stood at approximately $19.95 trillion when President Donald Trump first took office in January 2017 and reached $27.75 trillion by the end of his first term.

It then climbed to roughly $36.22 trillion during former President Joe Biden’s four-year presidency before increasing by another $3.8 trillion since Trump returned to office.

Debt increased by approximately $11.6 trillion across Trump’s two terms and by about $8.5 trillion under Biden.

Persistent budget deficits, pandemic-related borrowing, tax cuts, growing social program expenditures and rising interest costs have contributed to the increase.

The milestone is expected to heighten concerns about U.S. fiscal sustainability as debt-servicing costs take up a growing share of federal revenues.