* Helicopter crashed into soldier's vehicle
* Two Malian troops also injured
* France confirms gradual withdrawal of 4,000 troops
A Burkinabe soldier was killed when a Malian army helicopter crashed into his vehicle during a military exercise, a spokesman said on Thursday, underscoring the challenge for African forces to take over from France in the fight against Islamist rebels.
Malian army spokesman Modibo Nama Traore said the incident took place on Wednesday near the town of Diabaly in central Mali during a joint training exercise between France, Mali and the AFISMA force of African nations.
Two Malian troops were also injured when the helicopter crashed, slicing in two the pickup truck carrying the soldier from Burkina Faso.
"This unfortunate incident happened on the first day of the joint manoeuvre," Captain Traore told Reuters.
French Prime Minister Jean-Marc Ayrault confirmed on Thursday on a visit to Canada that France would begin a gradual withdrawal of its 4,000 troops in Mali from late April, handing responsibility to the AFISMA force.
However, concerns have been raised over the lack of equipment and logistical capabilities facing African armies operating in the region.
An EU mission has been deployed to train African forces but a donors conference for Mali held in Addis Ababa in January pledged just $455 million - roughly half the targeted amount.
France intervened dramatically in Mali on Jan. 11 to prevent an Islamist column sweeping southward towards the capital Bamako. Paris warned that Islamists' control over northern Mali gave them a launch pad to attack neighbouring African countries and the West.
Since then, a French-led operation has broken the al Qaeda-linked rebels' 10-month domination of northern Mali, driving them back into hideaways in the vast desert and in mountain caves.
Four French soldiers, 29 Chadian troops and 37 Malian soldiers have been killed in battles with the loose alliance of Islamist forces.
Other than the Chadian contingent, most AFISMA troops are based in southern Mali, away from the fighting.
France is pushing for the United Nations to approve a 10,000-strong peacekeeping force for Mali, once the mopping up of Islamist fighters is complete in the north, ideally before presidential elections scheduled for July.
The 6,300-strong AFISMA contingent would then be folded into the mandate, which would also include a heavily-armed force to counter any resurgent Islamist threat in Mali.
That rapid reaction unit, similar to a unit proposed for a U.N. mission in Democratic Republic of Congo, would be a departure from its typically more passive peacekeeper operations.