The previously secretive private military group Wagner on Friday opened its first official headquarters in Russia in the city of Saint Petersburg, AFP journalists said.

Yevgeny Prigozhin, who recently confirmed he founded the group whose fighters have been deployed to Ukraine as well as countries in Latin America and Africa, last week announced the opening of the office on his company Concord's social media page.

The shiny glass-fronted multistorey building topped with a big white "Wagner" sign opened on Friday.

People in camouflage clothing were wandering in the grey corridors of the building, looking at an exhibit displaying drones.

"The mission of the PMC Wagner Center is to provide a comfortable environment for generating new ideas to improve Russia's defence capability," Mr Prigozhin said in his statement.

Last month Mr Prigozhin put an end to years of rumours when he acknowledged he founded the group.

For years, the Wagner group has been suspected of playing a role in realising Moscow's overseas ambitions, with the Kremlin denying any links.

The force -- and its leader -- have taken an increasingly prominent role in the Ukraine offensive.