U.S. sees sharp rise in global terrorism deaths

"It applies classic insurgent strategies at the global level," he said, calling al Qaeda "the most immediate national security threat to the United States."

"A deeper trend is the shift in the nature of terrorism, from traditional international terrorism of the late 20th century into a new form of transnational non-state warfare that resembles a form of global insurgency," the report added.

The report listed the five countries that the United States has long branded as state sponsors of terrorism -- Cuba, Iran, North Korea, Sudan and Syria.

"Iran remains the most significant state sponsor of terrorism and continues to threaten its neighbors and destabilize Iraq by providing weapons, training, advice and funding to select Iraqi Shia militants," it said, saying Syria also lets militants "transit through its borders into Iraq."