U.S. President Barack Obama authorized sending surveillance aircraft, including drones, into Syrian airspace to gather intelligence on extremists ISIS militants, senior U.S. officials told The Wall Street Journal.

The Associated Press subsequently reported that the flights had already begun.

The flights are a further acknowledgment that the group also known as Islamic State (IS) is a threat beyond Iraq, and the operations would inform any decision to conduct airstrikes near the ISIS haven of Raqqa in eastern Syria.

Significantly, the missions will be carried out without coordination with or approval from the regime of Syrian President Bashar al-Assad. Officials noted that regime "air-defense systems in eastern Syria won't pose a threat because sensors are either sparsely located or inoperable," WSJ reports.

ISIS militants have consolidated their grip on northeast Syria by capturing the Tabqa air base and other remaining regime-held military bases in the Raqqa province.

Top U.S. military officials and experts have acknowledged that ISIS control of vast territory in Syria provides a safe haven for the group to conduct operations in both Syria and Iraq.

"Can they be defeated without addressing that part of the organization that resides in Syria? The answer is no," U.S. Chairman of the Joint Chiefs of Staff General Martin E. Dempsey, told reporters at the Pentagon last week.

"If ... conditions continue as they are, I believe the IS will largely expand the territory under its control in Syria," Charles Lister of the Brookings Institution told Der Spiegel.

Airstrikes on ISIS positions would signal a change of course in Obama's Syria policy, which has been characterized by active non-involvement.

Paul Salem of the Middle East Institute notes that potential strikes "could have multiple effects: It would help protect the Kurds and ‘moderate’ opposition from major ISIS or Nusra attempts to conquer their territories; it would directly empower these opposition groups against their radical jihadi foes; and it would give a great boost of morale to these groups, many of whom had perhaps rightly concluded that they had been abandoned."

Administration officials told The Guardian that the favored long-term strategy to defeat ISIS is to train moderate Syrian rebels to fight both ISIS and the regime. But the non-jihadist rebels in the Free Syrian Army are now being decimated by both jihadists and the regime after years of being brushed aside as "former doctors, farmers, pharmacists, and so forth" by Obama.

