"I can confirm that I have received the ruling, under which Janez Janša gets two years in prison and two other co-defendants 22 months," prosecutor Andrej Ferlinc told reporters in Ljubljana.

Janša was sentenced last June and appealed the verdict. He had denied taking money in the planned purchase of 135 armoured vehicles from Finnish defence group Patria while he was prime minister. The deal was eventually cancelled. The official STA news agency quoted the higher court ruling as saying "the complaints of the defendants' lawyers were dismissed as unfounded and the first-instance ruling was confirmed".

A prison sentence for the opposition leader further complicates the outlook for the small euro zone member, plunged into fresh turmoil after Prime Minister Alenka Bratušek lost leadership of her centre-left PS party at a weekend congress. The move is widely expected to bring down her government and trigger an early election. Bratušek is expected to reveal whether she will quit the government on Tuesday.

Janša's conservative SDS party is the second strongest in the current parliament with 26 deputies in the 91-seat assembly. Janša championed Slovenia's drive to secede from Yugoslavia in 1991 and was prime minister from 2004 to 2008 and again for a year until March 2013. His centre-right government fell in February last year, after an anti-corruption commission said Janša was unable to explain the origins of a significant part of his income over several years.

Six people in Finland are being prosecuted over the same arms deal and an Austrian court has convicted an Austrian citizen of corruption. The 278 million-euro ($363 million) contract was scrapped in 2012 after the allegations surfaced. Prosecutors in Finland said last June they would charge three former Patria executives with bribing government officials in Slovenia's neighbour Croatia. The Finnish government owns around 73 percent of Patria while European Aeronautic Defence and Space Company (EADS) holds some 27 percent.