A drone sits at a French army base in Niamey, Niger. France and the United States have ramped up their cooperation in Africa to counter terrorist threats. (Martin Bureau/AFP/Getty Images)

The Pentagon is preparing to open a drone base in one of the remotest places on Earth: an ancient caravan crossroads in the middle of the Sahara.

After months of negotiations, the government of Niger, a landlocked West African nation, has authorized the U.S. military to fly unarmed drones from the mud-walled desert city of Agadez, according to Nigerien and U.S. officials.

The previously undisclosed decision gives the Pentagon another surveillance hub — its second in Niger and third in the region — to track Islamist fighters who have destabilized parts of North and West Africa. It also advances a little-publicized U.S. strategy to tackle counterterrorism threats alongside France, the former colonial power in that part of the continent.

Although the two allies have a sporadic history of quarreling when it comes to military action, U.S. and French troops have been working hand in glove as they steadily expand their presence in impoverished West Africa. Both countries are alarmed by the presence of jihadist groups, some affiliated with al-Qaeda, that have taken root in states whose governments are unable to exert control over their own territory.

In Niamey, Niger’s capital, U.S. and French forces set up neighboring drone hangars last year to conduct reconnaissance flights over Mali, where about 1,200 French soldiers are trying to suppress a revolt that erupted in 2012.

View Graphic Map showing where the United States and France have expanded their military presence in West Africa

In Chad, the U.S. Air Force has been flying drones and other aircraft from a French military base to search for hundreds of schoolgirls abducted by Islamic militants in northern Nigeria.

The White House approved $10 million in emergency aid on Aug. 11 to help airlift French troops and provide midair refueling for French aircraft deployed to West Africa. Analysts said the monetary sum was less important than what it symbolized: U.S. endorsement of a new French plan to deploy 3,000 troops across the region.

“We have this confluence of interests where both countries are working much more closely than would have been thought possible just a couple of years ago,” said J. Peter Pham, an expert on African security at the Atlantic Council, a Washington think tank.

The cooperation is a turnabout from early 2013, when France deployed troops to northern Mali to try to prevent the country from breaking apart. The Obama administration was slow to respond to requests to provide crucial logistical support to French troops, a reflection of how the two countries have sometimes worked at cross-purposes on security policy.

France is protective of its economic and political interests in West Africa. Yet in 2008 it shrank its military presence on the continent and instead opened a base in the Persian Gulf, an area that the U.S. military sees as its sphere of influence. Around the same time, the Pentagon created an Africa Command and expanded its training partnerships with French-speaking countries on the continent, to the annoyance of some officials in Paris.

In July, however, French President François Hollande announced that his country would again bulk up its forces in West Africa. Under Operation Barkhane (a term for a crescent-shaped sand dune), France will permanently deploy 3,000 troops at bases in Mali, Chad, Niger and Burkina Faso.

French leaders consulted closely with U.S. officials before the operation. Pentagon officials said they were happy to let France take the lead on the ground, enabling the U.S. Air Force to focus on drone flights and other airborne missions that it is better equipped to handle.

At the start of a news briefing on Tuesday, Pentagon press secretary Rear Adm. John Kirby gave more details about U.S. strikes in Iraq and Somalia. He said the Pentagon is monitoring reports of the execution of an American journalist by Islamic State militants. (AP)

“They have a similar strategy and aim about what they are doing,” said Sarah Covington, a sub-Saharan Africa analyst at IHS Country Risk, based in London. “The French have been in that region for decades now and have an extremely strong presence.”

The new base in Agadez will put U.S. drones closer to a desert corridor connecting northern Mali and southern Libya that is a key route for arms traffickers, drug smugglers and Islamist fighters migrating across the Sahara.

The city was once a magnet for ad­ven­ture tourists from Europe seeking a taste of nomad culture. But rebellions by Tuareg tribesmen in recent years and an influx of Islamists have made it a more dangerous place.

In a written response to questions, Benjamin A. Benson, a spokesman for Africa Command, called Agadez “an attractive option” for a base, “given its proximity to the threats in the region.”

In February, records show, the Pentagon’s Defense Logistics Agency solicited bids for the delivery of more than 7 million gallons of jet and diesel fuel to Agadez later this year. In July, the Air Force posted a separate solicitation to upgrade the Agadez airport runway, a project estimated to cost between $5 million and $10 million. Documents cautioned that the project was still awaiting authorization from the government of Niger.

The next month, Mahamadou Issoufou, the president of Niger, traveled to Washington to attend the Obama administration’s U.S.-Africa Leaders Summit. On Aug. 7, the day after the summit, Issoufou gave final approval to the Agadez drone base during a meeting with Deputy Defense Secretary Robert Work; Army Gen. David Rodriguez, the leader of Africa Command; and several other participants, according to Nigerien and U.S. officials.

Benson, the Africa Command spokesman, declined to say how many drones or U.S. military personnel will be deployed to Agadez, saying the operation is still in the planning stages.

The Pentagon continues to broaden its drone operations in Africa, despite growing demand for the aircraft in other conflict zones.

Since June, surveillance drones have been redeployed from bases in the Middle East to fly dozens of sorties a day over Iraq. The aircraft are also sorely needed in Afghanistan as the U.S. military draws down its forces there, as well as for counterterrorism missions in Yemen and Somalia.

The Pentagon also keeps watch over northern Libya with Predator drones that cross the Mediterranean from a U.S. base in Sicily, Italy.

The U.S. military would like to increase its reconnaissance flights over Libya, where Islamist factions and tribal militias have shattered the country. Having a drone base in Agadez will make it easier to reach the vast desert terrain in southern Libya, where many itinerant Islamist fighters have regrouped after being expelled from Mali, according to security analysts.

It is unclear whether the Pentagon will continue to operate drones from Niamey, the capital, about 500 miles southwest of Agadez, though some officials said it was unlikely. About 120 U.S. troops are deployed there at a Nigerien military base adjacent to the international airport.

French forces keep their own, small drone fleet in nearby hangars. It consists of two U.S.-built Reaper aircraft, purchased last year, and an older-model Harfang drone.

In contrast to the U.S. military, which is secretive about its drone operations, the French have been eager to show off their spy aircraft. When Hollande visited Niamey in July to tout Operation Barkhane, news photographers were permitted inside the French drone hangar.