Residents and a Malian Army official said UN forces carried out an airstrike for the first time against rebels in northern Mali, killing seven people.
The National Movement for the Liberation of Azawad (MNLA), an ethnic Tuareg rebel group, admitted having suffered “losses” but gave no casualty count.
The group said later that it would halt security cooperation with the UN peacekeeping force.
The UN force said its soldiers had repeatedly come under fire from heavy arms in the last several days.
The UN has about 9,000 peacekeepers in Mali, which was recovering from a coup and an Islamist insurgency that was rolled back by French military interventions two years ago.
The UN contingent, which arrived 18 months ago, regularly come under attack and has lost several soldiers over the past few months.