India, Nov. 15 -- US Transportation Secretary Sean Duffy has blamed previous administrations and Congress for the outdated air traffic control system after a nationwide flight disruption on Friday. He has called for another $50 billion to upgrade the system, saying the $12.5 billion already approved by Congress is not enough.

Transportation Secretary Sean Duffy has blamed earlier administrations and Congress for the poor state of America's air traffic control system. His comments came after a nationwide ground stop on Friday that stopped all US flights and disrupted air travel across the country.

Speaking to CNN's "State of the Union" on Sunday, Duffy again asked Congress to approve another $50 billion to upgrade the system. He said yea...