The pullout, demanded by Niger's military rulers, started last week after the July ouster of president Mohamed Bazoum, a key ally of Paris, threw France's strategy for the Sahel region into disarray.

"The objective of presidential announcements of a departure on December 31 will be met," said French general Eric Ozanne at a joint press conference with Niger's Colonel Mamane Sani Kiaou in the capital Niamey.

The Nigerien colonel added that 282 soldiers had already left the country "as of today".

"Two large convoys of military vehicles that were in the northern zone" have left, said Ozanne, adding that a number of convoys carrying "non-sensitive equipment" had begun to leave.

He said these did not include "armament" or "transmission" equipment.

"The big logistical flows will really start next week," he added, noting that 2,500 containers were due to be shipped out of the country.

"This is being handled by an outsourced civilian carrier and is totally transparent, especially for the local population, who will just see trucks with containers," he said.

The first French road convoy of troops withdrawing from Niger arrived in neighbouring Chad's capital N'Djamena on Thursday, after 10 days on the road.

N'Djamena is the site of France's military headquarters for the whole Sahel region, with around 1,000 troops there.

"Chad is only a transit country, it's not a re-articulation of our operation from Niger to Chad," said Ozanne.

From Chad, French troops can leave by air with their most sensitive equipment. However, most will have to be moved by land and sea.

The journey "has been perfectly planned and prepared by the Nigerien authorities, and the messages passed on to the population have been perfectly received and heard," said Ozanne.

"Disengagement is taking place in a coordinated manner, we have the same objective," he added.

"We don't always agree on everything, but we talk to each other, we work things out, we find compromises, so it's all happening in the spirit of professionalism and with the aim of finding solutions," Ozanne said.

Niger's colonel Kiaou said "we've worked together for years".

"We've asked them to leave, so we'd like everything to go smoothly and for them to be able to return to Chad in complete safety," he added.