Babaryka was considered one of the strongest opponents to authoritarian leader Lukashenko, who has been in power for close to three decades.
A court in Belarus sentenced former Belarusian presidential contender Viktar Babaryka to 14 years in prison on corruption charges.
Babaryka's team said before Tuesday's ruling that the charges against their client had been fabricated to thwart his political ambitions.
Babaryka, the former head of Belgazprombank, was arrested last June as he was trying to register as a candidate to run against authoritarian leader Alexander Lukashenko in a presidential vote critics and observers say was massively rigged.
#Belarus Viktar Babaryka, the most influential potential candidate and a former banker has been sentenced to 14 years in jail. His only guilt is that he decided to run against #Lukashenko. He immediately gathered immense support and is still the most popular politician in Belarus pic.twitter.com/0XYcd2iGyS— Hanna Liubakova (@HannaLiubakova) July 6, 2021
Prosecutors had requested that Babaryka, who maintains his innocence, be sentenced to 15 years in jail for his alleged offences.
After Babaryka was barred from running and detained, Maria Kolesnikova, one of his allies, joined forces with two other women, Sviatlana Tsikhanouskaya and Veronika Tsepkalo, to lead the opposition's campaign.
Kolesnikova is now jailed in Belarus, Tsepkalo has fled abroad, and Tsikhanouskaya, who ran against Lukashenko and has since emerged as the opposition's most prominent figure at liberty, is trying to undermine Lukashenko from neighbouring Lithuania.
Belarusian authorities have cracked down on the anti-government protests that erupted in the wake of the vote, prompting a flurry of Western sanctions against Minsk.
Lukashenko, who has been in power since 1994, denies electoral fraud.
Most of the people weren't allowed in the room where #Babaryka was on trial. Those who managed to come inside showed hearts to Viktar. This was his most recognisable gesture during his campaign. pic.twitter.com/mqb7ukzkI9— Hanna Liubakova (@HannaLiubakova) July 6, 2021