A patrol of the Niger national Police drives past the French Embassy in Niamey on August 28, 2023. AFP
"The ambassador and six colleagues left Niamey around 4:00 am (0300 GMT)," a diplomatic source from the French embassy said.
A source in the Niger interior ministry confirmed the departure and said the plane was headed towards Chad.
It comes two months after a coup in Niger ousted its pro-Paris president and prompted a souring in relations between France and its former colony.
On Sunday, French President Emmanuel Macron announced in a TV interview that France's ambassador to Niger Sylvain Itte would leave "in the next hours" but gave no details.
Niger's military leaders -- who overthrew the democratically elected president Mohamed Bazoum on July 26 -- welcomed the announcement but said they were waiting for it to be followed up by official actions.
They had told Itte to leave the country after they overthrew Bazoum and took away the envoy's diplomatic immunity and visa.
But a 48-hour ultimatum for him to go, issued in August, passed with him still in place, as the French government refused to comply or to recognise the military regime as legitimate.
Paris had said that only Bazoum's deposed government could order the envoy out.
Born in the Malian capital Bamako in 1959, Itte has been in the post as ambassador to Niger for a year.
His diplomatic career spans 35 years and he was previously ambassador to Uruguay and Angola.
Military pullout
Macron also announced in his Sunday TV interview that French troops would withdraw from Niger in "the months and weeks to come" with a full pullout "by the end of the year" -- another demand of the Niger regime.
The French president, who had sought to make a special ally of Niger, said military cooperation was "over".
France keeps about 1,500 soldiers in its former West African colony as part of an anti-jihadist deployment in the Sahel.
The coup against Bazoum was the third such putsch in the region in as many years, following similar actions in fellow former French colonies Mali and Burkina Faso in 2021 and 2022, respectively.
They too forced the pullouts of French troops.
Macron said on Sunday that Niger's post-coup authorities "no longer wanted to fight against terrorism".
He also reaffirmed France's position that Bazoum was being held "hostage" and remained the "sole legitimate authority" in the country.
The elected president has remained confined in the presidential palace with his wife and son.
Niger welcomed Macron's announcement on Sunday as "a new step towards sovereignty" but has said the timeframe for the pullout "must be set out in a negotiated framework and by mutual agreement".
Niger, like Burkina Faso and Mali, has been targeted by jihadist attacks for several years.
In recent weeks, tens of thousands of people have joined demonstrations and gatherings in Niamey calling for the withdrawal of the French troops from the country.
The United States, which has some 1,100 military personnel in Niger, has said it will "evaluate" its future steps on the crisis following France's announcement.
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