Russia's Wagner mercenary group said on Monday that its fighters and Malian soldiers took losses in heavy fighting against Tuareg rebels near Mali's border with Algeria.

Mali, where military authorities seized power in coups in 2020 and 2021, is battling a years-long Islamist insurgency.

It has said Russian forces there are not Wagner mercenaries but trainers helping local troops with equipment bought from Russia.

The rebel movement, the Permanent Strategic Framework for Peace, Security and Development (CSP-PSD), said on Saturday that it had seized armoured vehicles, trucks and tankers in the fighting at the border town of Tinzaouaten.

Wagner, in a rare statement, said its forces had fought alongside Mali soldiers from July 22-27 and that Wagner fighters were commanded by Sergei Shevchenko, whose callsign was "Pond", near Tinzaouaten.

"On the first day, the 'Pond group' destroyed most of the Islamists and put the rest to flight," Wagner said on Telegram.

"However, (an) ensuing sandstorm allowed the radicals to regroup and increase their numbers to 1,000 people."

Wagner said its fighters again repulsed an attack but that under massive rebel fire, there had been losses among Wagner and the Malian army.

The last message from the Wagner group on July 27 was: "The three of us stayed. We continue to fight."

Wagner said Shevchenko was killed.

The Malian army said in statements at the weekend that two of its soldiers had been killed and 10 injured. One of its helicopters had crashed in Kidal on Friday while on a routine mission but no one was killed, it said.