Paris - Rwanda accuses France of having played an indirect role in its 1994 genocide, a charge Paris categorically denies.
The declassification by France on Wednesday of documents relating to the genocide may shed light on unanswered questions over the mass killings, which claimed 800 000 lives.
In the early 1990s France was an ally of Hutu president Juvenal Habyarimana, who faced hostility from Tutsi rebels from the Uganda-based Rwandan Patriotic Front (FPR).
Also Read: Rwandan leader complains of rebels in DRC
After an FPR offensive launched on October 1 1990, Paris sent around 300 soldiers to Rwanda. Former colonial power Belgium also took part in the operation, the official objective of which was to protect foreign citizens.
While Belgium withdrew its troops one month later, the French forces remained in an advisory capacity.
In 2008, a Rwandan committee of inquiry accused the French forces of having helped set up extremist Hutu militias, known as interahamwe, who spearheaded the genocide.
A French committee of inquiry in 1998 ruled that "errors of judgement" had been made by France in Rwanda.
After August 1993 accords struck in Arusha, Tanzania, which shared out power between Hutus and Tutsis, and the deployment of a UN force, the French troops withdrew.
The Rwandan probe charged that from April 7 1994, the day after the fatal attack on the plane carrying Habyarimana which unleashed the genocide, the French evacuated several members of the Hutu regime.
They included the president's widow, Agathe, who is herself accused of playing a major role in the preparation of the massacres.
Also Read: Rwanda urged to take action over BBC genocide documentary
France's UN-mandated Operation Turquoise, launched on June 22 1994 involved 2 500 troops and was aimed at establishing a safe humanitarian zone in the south.
The current Rwandan Tutsi leader Paul Kagame believes that the operation was a back door, allowing thousands of Hutu genocide suspects to escape to what was then Zaire and has accused French troops of being "accomplices", and "players" in the massacres.
In the emblematic town of Bisesero the French were accused of leaving escaping Tutsis at the mercy of the Hutu killers for three days before intervening.
Paris insists it did not deliver weapons to Hutu extremists, but a French policeman is accused of signing a May 1994 arms contract worth $3m with the Hutu government.
France has carried out a judicial probe into whether the Hutus or Tutsis carried out the attack on Habyarimana's plane.
French anti-terrorism judge Jean-Louis Bruguiere accused members of current leader Kagame's family, issuing arrest warrants for nine of them in 2006.
Ballistic experts estimate that the fatal shots likely come from a Hutu camp.
France has also been criticised for slowness in arresting and prosecuting suspected genocide perpetrators living on its soil.
Two former Rwandan mayors are, however, to face court, opening the way to the staging of a second trial in France on the genocide.