Thirteen soldiers from Chad have died while fighting in northern Mali.
It is the largest death toll on side of the French and African troops fighting the Islamist rebels.
Sixty-five Islamist rebels were also killed.
Two thousand troops from Chad are fighting alongside 4,000 French troops.
The foreign offensive to assist Mali’s government and push the rebels out of their strongholds in the north has been going on for six weeks.
Intense battles continue in the town of Gao. It is supposedly back under government control, but the rebels refusing to back down.
One hundred US soldiers have been deployed to Niger to help coordinate intelligence sharing with the French as they fight in Mali.
France plans to start withdrawing troops next month, but there are fears that with the rebel counter-attacks, French soldiers could get drawn into a guerilla war.
Mali’s army remains weak and divided and the African forces due to take over from the French are not yet in place.