US national debt has crossed $40 trillion for the first time, raising concerns over borrowing costs, federal spending, deficits and the long-term fiscal outlook.

The federal debt reached $40 trillion as the government adds red ink at a rapid rate. That's leading nervous investors to demand higher interest rates —pushing up borrowing costs…

Federal debt has mounted amid tax cuts and trillions in pandemic spending, adding to the nation's interest payments.

The national debt is now over $40 trillion, a historic high that economists warn is bad news for the United States.