A photo taken on May 23, 2021 shows a Boeing 737-8AS Ryanair passenger plane (flight FR4978, SP-RSM) from Athens, Greece, that was intercepted and diverted to Minsk on the same day by Belarus authorities. Photo: AFP

A court in Belarus on Tuesday sentenced one of strongman Alexander Lukashenko's leading critics to 14 years in prison on fraud charges. 

Former banker Viktor Babaryko was arrested in June in 2020 ahead of a disputed presidential election that sparked nationwide demonstrations which gripped the ex-Soviet country for months. 

Babaryko had planned to run for president and was considered one of the strongest opponents to incumbent Lukashenko, who has been in power for close to three decades.

Babaryko was accused of receiving bribes and "laundering funds obtained by criminal means" when he was head of Belgazprombank, the Belarusian branch of a bank belonging to Russian energy giant Gazprom. 

Prosecutors had requested a 15-year sentence, the maximum possible punishment. Babaryko denied any wrongdoing throughout his trial.

Belarus's Supreme Court on Tuesday handed down a 14-year sentence that is not subject to appeal, an independent journalist reported from the court.

Babaryko's Twitter account, which is run by supporters, said he would serve the 14 years "in a maximum security colony." Babaryko was also fined the equivalent of about 45,000 euros ($53,000) and barred from holding senior official positions.

Seven other defendants in the case, including several Belgazprombank executives, were prosecuted on the charges.

They all pleaded guilty and on Tuesday were sentenced to terms of between three and six years.

The leader of Babaryko's presidential campaign, Maria Kolesnikova, and his lawyer Maxim Znak are also in custody and have been charged with "conspiracy to seize power." Tens of thousands took to the streets of Belarus for weeks to protest the result but were met with a harsh police crackdown. Authorities have also clamped down on independent media, jailing journalists over their coverage of the protests and withdrawing accreditation from foreign outlets.

Western powers have responded with a wave of sanctions against Lukashenko's regime, especially after a Ryanair passenger flight between European capitals was grounded in late May in Minsk and authorities detained opposition activist Roman Protasevich and his girlfriend who were on board.