Lawyers for Niger's ousted president on Friday rejected claims by the new military rulers that he had tried to escape, as former colonial ruler France said its forces would be gone from the West African country by year's end as planned.

Since he was toppled by the military on July 26, Niger's president Mohamed Bazoum had been held at his residence in the heart of the presidential palace along with his wife and son.

The military regime said late on Thursday that Bazoum had "tried to escape" with his family, two cooks and two security agents.

The escape plan involved getting to a hideout on the outskirts of the capital Niamey before taking helicopters "belonging to a foreign power" towards Nigeria, regime spokesman Amadou Abdramane said on state television.

The bid failed and "the main actors and some of the accomplices" were arrested, he added.

But a lawyers collective on behalf of Bazoum said it strongly rejected the "fabricated accusations" against him.

Bazoum, his wife and son are being "held incommunicado, without access to lawyers or the outside world", Mohamed Seydou Diagne, coordinator of the collective, said in a statement sent to AFP in Abidjan.

On Friday, a doctor was refused access as he brought the family food, he added.

Being held "incommunicado", the lawyer said, was "a new red line which has been crossed by a junta which continues to violate the fundamental rights of our client".

Diagne said Bazoum's entourage had not had any news from him since overnight Wednesday to Thursday.

French President Emmanuel Macron late Friday expressed "concern over the uncertain situation" facing Bazoum and called "for his immediate release and that of his wife and son".

Last month, Bazoum's lawyers said he had filed a legal case with a court of the Economic Community of West African States against those who deposed him.

They also said they were taking his case to the UN Human Rights Council.

- 'Coordinated manner' - 

The French army meanwhile said its 1,500 troops in Niger would leave by December 31, in line with the timeframe announced by Macron late last month.

Demanded by Niger's military rulers following the coup, the pullout started last week.

The objective "will be met", commander of France's forces in the Sahel General Eric Ozanne told a joint press conference in Niamey with Niger's Colonel Mamane Sani Kiaou, who announced that 282 soldiers had already left.

"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.

"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. 

The French forces were based in Niamey and western Niger to battle fighters linked to the Islamic State group and Al-Qaeda, bringing with them fighter jets, drones, helicopters and armoured vehicles, as well as the equipment to support them.

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.

"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.

It is the third time in 18 months that French troops have been sent packing by a former African colony, dealing a severe blow to France's influence on the continent and prestige on the international stage. 

Relations between Paris and Niamey have been tense since the coup, but the two military chiefs struck a conciliatory tone Friday.

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

Niger's colonel Kiaou said: "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."

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