The diversion of the plane was roundly condemned by other Western allies.
Berlin, London and Brussels summoned the Belarusian ambassadors, as exiled opposition leader Svetlana Tikhanovskaya called for an independent probe, new sanctions and for Minsk to be excluded from worldwide aviation bodies.
"I condemn the forced landing of the civilian flight by the Belarusian regime under the politically motivated pretext of a terrorist threat", Slovakia's Foreign Affairs Minister Ivan Korčok (SaS nominee) commented. They instead accused the West of making unfounded claims for political reasons.
Last year, Protasevich was an editor for Poland-based Nexta Live, which played an important role in broadcasting huge opposition protests against Belarusian President Alexander Lukashenko via the Telegram messenger app. Ursula von der Leyen, President of the EU Commission says in a statement: "Any violation of global air transport rules must bear consequences".
U.S. Secretary of State Antony Blinken said the plane's diversion was "shocking", while Lithuanian President Gitanas Nauseda called it a "state-sponsored terror act".
Foreign Minister Sergei Lavrov said Minsk was taking an "absolutely reasonable approach" while ministry spokeswoman Maria Zakharova mocked the Western indignation.
An unacceptable enforced landing of a commercial plane breaches worldwide travel and requires a strong response.
Foreign Secretary Dominic Raab said further sanctions are being considered against the Lukashenko administration - including the suspension of energy pipelines in Belarus - and Belarus's ambassador in London had been summoned for a dressing down. Tikhanovskaya said in her telegram channel.
The listing said he was accused of organising mass riots while working at Nexta.
His name is Roman Protasevich, and on Sunday, he drew worldwide attention because the Belarusian government and its authoritarian leader went to extraordinary lengths to stop him. Like thousands of other dissidents, Pratasevich fled to Lithuania.
Mr Protasevich left the Nexta project previous year. Additionally, the aircraft was still at cruising altitude at the time it was diverted, which is out of the ordinary, as flight history shows FR4978 normally beginning its descent into Vilnius approximately 177 km from VNO airport.
Officials later said no explosives had been found on board while the deputy air force commander said the plane's crew made the decision to land in the Belarus capital.
"I think the sanctions need to be fully thought through in terms of consequences, but I think this is an incident that is on the upper end of the scale in terms of something that needs a very strong sanction-based response".
Ryanair's CEO Michael O'Leary described the move as "a case of state-sponsored hijacking. state-sponsored piracy".
Carriers and aviation authorities are concerned about safety after Ryanair flight 4978 was ordered to divert to Minsk by Belarusian air traffic control on Sunday over a supposed security alert.
A senior transport official, Artem Sikorsky, told journalists that authorities in Minsk had received a letter claiming to be from Hamas threatening to blow up the plane over Vilnius unless the European Union renounced support for Israel.
"He just turned to people and said he was facing the death penalty".
His girlfriend Sofia Sapega - a Russian citizen and law student at the European Humanities University (EHU) in Lithuania - was arrested along with him, her university confirmed on Monday.