Bosnians will head to the polls in October but fears are growing that Russia, which is waging war in Ukraine, is fanning the embers of separatism in the deeply divided Balkan nation.

Since the end of the war that claimed around 100,000 lives between 1992 and 1995, Bosnia has been split between a Muslim-Croat federation and a Serb entity -- known as Republika Srpska (RS).

Active since 2004, the EU's EUFOR Althea operation is the successor of NATO's peacekeeping missions in the country.

Comprising soldiers from more than 20 nations, the deployment last included German soldiers in 2012.

Germany will send a maximum of 50 soldiers back to the country, said government spokesman Steffen Hebestreit, adding that the mandate is limited to a year.

With Bosnia's Serb leader Milorad Dodik increasingly vocal about his secessionist aims, the EU has nearly doubled its military presence in Bosnia in what EU foreign policy chief Josep Borrell calls a "precautionary measure".

The decision to boost the EU's deployment from 600 troops by 500 also came on February 24 -- the same day that Russia's invasion of Ukraine began.

Dodik has made no secret about his admiration and close ties with Russian President Vladimir Putin and his action is widely believed to have the backing of the Kremlin.