The White House confirmed reports Monday that the Obama administration is working closely with countries in Northern Africa to try to combat threats from the Islamic State of Iraq and Syria and other extremist activity in Libya, but declined to say specifically whether the U.S. is trying to establish a drone base to improve surveillance capabilities.

"There are obviously a number of details I can't get into from here," presidential press secretary Josh Earnest told reporters Monday. "The U.S. coordinates closely with countries throughout Northern Africa and Europe who share our concerns about extremists in Libya."

The White House does not publicly acknowledge the U.S. government's use of drones to kill extremists, so Earnest had to parse his words carefully.

He cited the "terrible terrorist attack" in Tunisia just 10 days ago as an example of the ongoing concern about the surge of Islamic State activity in the region.

"We'll continue to coordinate both on security matters and intelligence matters with countries in the region," he said. He said the United States recently signed a security agreement with Tunisia, and noted Washington's "longstanding security arrangement" with Egypt.

The Wall Street Journal reported Monday that the U.S. wants to establish a drone base in North Africa to provide U.S. military and intelligence agencies real-time information about the Islamic State's movements and activity in Libya.

So far, however, no North African country has agreed to allow a U.S. drone base on its soil, the WSJ said, citing senior U.S. officials.

Militants have taken advantage of civil unrest in Libya and are gaining ground while two rival governments vie for control.