Russia's President Vladimir Putin has spoken for the first time about the plane crash in which it is said that Wagner boss Yevgeny Prigozhin died.

He said news of his presumed death came after his return from Africa.

"Only yesterday [Wednesday] returned from Africa. He met certain official persons there," the Russian leader said.

In recent days the Wagner head is believed to have been present in West Africa - where Western analysts fear the group was seeking to widen its reach into other countries, including Niger, where a coup has just taken place.

Wagner is a key pillar of Russian foreign policy, with its forces helping to prop up governments in Syria, Mali, the Central African Republic (CAR) and Libya in exchange for lucrative mining rights.