WASHINGTON -- The U.S. military command in Africa is planning to establish a drone base in northwest Africa to increase unarmed surveillance missions on the local affiliate of Al-Qaida and other Islamist extremist groups that Western officials say pose a growing menace to the region.

For now, officials say they envision flying only unarmed surveillance drones from the base, although they have not ruled out conducting missile strikes at some point if the threat worsens.

If the base is approved, its most likely location would be in Niger, a largely desert nation on the eastern border of Mali, where French and Malian troops are now battling Al-Qaida-backed fighters who control the northern part of that country. The U.S. military's Africa Command is also discussing options for the base with other countries in the region, including Burkina Faso, officials said.

The immediate impetus for a drone base in the region is to provide surveillance assistance to the French-led operation in Mali.

"This is directly related to the Mali mission, but it could also give Africom a more enduring presence for ISR," one U.S. military official said Sunday, referring to intelligence, surveillance and reconnaissance.

A handful of unarmed Predator drones would carry out surveillance missions in the region and fill a need for more detailed information on a range of regional threats -- including militants in Mali and the unabated flow of fighters and weapons from Libya -- that intelligence analysts say has been sorely lacking.

The U.S. military has a very limited presence in Africa, with only one permanent base, in Djibouti, more than 3,000 miles from Mali. A new drone base in northwest Africa would join a constellation of small air bases in recent years on the continent, including in Ethiopia, for surveillance missions flown by drones or turboprop planes designed to look like civilian aircraft.

The Africa Command's planning still needs approval from the Pentagon and eventually from the White House, as well as from Nigerian officials.

But in Niger on Monday, the two countries reached a status-of-forces agreement that provides legal protection to U.S. troops in the country, including any who might deploy to a new drone base. If approved, the base could ultimately have as many as 300 U.S. military and contractor personnel, but it would probably begin with far fewer people than that, military officials said.

Some Africa specialists expressed concern that setting up a drone base in Niger or in a neighboring country, even if only to fly surveillance missions, could alienate local people who may associate the distinctive aircraft with deadly attacks in Pakistan, Yemen and Somalia.

Niger's president, Mahamadou Issoufou, has expressed a willingness to establish what he called in a recent interview "a long-term strategic relationship with the U.S."

"What's happening in northern Mali is a big concern for us because what's happening in northern Mali can also happen to us," Issoufou said in an interview at the presidential palace in Niamey, Niger's capital, the day before French troops swept into Mali on Jan. 11 to blunt the militant advance.

Gen. Carter Ham, the head of Africa Command, who visited Niger this month to discuss the country's security cooperation with the United States, declined to comment.