Burkina Faso asked France to move its troops out of the country within a month, according to a diplomatic letter from the authorities there to Paris obtained by AFP Sunday.
President Emmanuel Macron on Sunday said Paris was awaiting clarifications from Burkina Faso after the African country's military regime said it wanted French troops to leave within a month.
Macron urged "a lot of prudence", saying there was "great confusion" over the remarks reported in the media and said military junta leader Ibrahim Traore needed to take a public stance.
"We are waiting for clarifications on the part of Mr Traore," he told reporters.
The foreign ministry letter, dated last Wednesday, ends the 2018 agreement under which French troops were stationed there, and sets a deadline of a month for their departure.
AFP obtained the letter from a Burkinabe diplomatic source, who was not able to say whether or not France had acknowledged reception of the letter.
Asked about the letter, the French president's office said it was still waiting for confirmation of the Burkinabe position at "the highest level", reiterating Macron's statement earlier Sunday.
Burkina Faso's state news agency reported the details of the request late on Saturday, and a source close to the government confirmed their account to AFP.
The source clarified that it was "not the severance of relations with France. The notification only concerns military cooperation agreements".
- Deteriorating relations -
France has 400 special forces soldiers stationed in junta-ruled Burkina to battle a jihadist insurgency, but relations have deteriorated in recent months.
Since the current military regime seized power in September there have been several demonstrations calling for the departure of the French ambassador, and the French troops there.
There are signs that Burkina Faso, like its neighbour Mali, is turning towards Russia as a partner.
"Russia is a reasonable choice in this dynamic," Burkinabe Prime Minister Apollinaire Kyelem de Tembela said last week following a meeting with the Russian ambassador.
"We think our partnership has to be strengthened," he added.
Kyelem de Tembela visited Moscow early in December.
Burkina Faso is reeling from a jihadist insurgency that swept in from neighbouring Mali in 2015.
Traore seized power in a coup in late September, in the second military coup in the country in eight months.
France has been concerned about a repeat of its disastrous falling-out with Mali, from which it pulled out troops last year.
If French forces were to pull out of the country, Paris's preferred option appears to be to redeploy its forces in the south of neighbouring Niger, where nearly 2,000 of its soldiers are already stationed.