The European Union is readying to seal off its airspace and airports to Belarusian airlines after a flight between two EU states was forcibly diverted to Minsk.
In a statement published late on Monday, the bloc instructed officials to "adopt necessary measures to ban overflight of EU airspace by Belarusian airlines and prevent access to EU airports."
The 27 leaders also urged all EU-based carriers to avoid flying over Belarusian territory in the joint declaration, approved at a summit in Brussels.
Once implemented, state airline Belavia will not be able to fly to a host of cities, including to Berlin, Paris and Brussels. It will also likely have to re-route its flights to, for example, Tunisia, as the most direct flight path crosses EU air space.
The member states demanded the release of detained Belarusian opposition journalist Roman Protasevich and his partner Sofia Sapega.
The incident, which interrupted a Ryanair flight between EU countries Greece and Lithuania on Sunday, leapt onto the agenda of a Brussels summit at the last minute and soured relations with the authoritarian government even further.
Dissident journalist Protasevich, who had been on board, was taken into custody after the flight was diverted to the Belarusian capital on allegations of a bomb threat. No bomb was found.
The 26-year-old has been taken into pre-trial detention, Belarusian authorities confirmed on Monday.
The EU also decided to sanction Belarusian individuals after the forced diversion, which some leaders have slammed as a "state hijacking." A list of individuals and companies will be drawn up at a later stage.
According to a tweet by European Commission President Ursula von der Leyen, which was sent out before the meeting, this could include targeting the Belarusian aviation sector, businesses that support the country's "regime" and people involved in the diversion.
In addition, a package of economic sanctions should be prepared, the EU statement continued.
The punitive measures were agreed on relatively quickly after leaders headed into their meeting on Monday evening, with multiple premiers having publicly voiced their support for sanctions throughout the day.
Lithuania's President Gitanas Nauseda called the forced landing "abhorrent." Similarly, Irish Prime Minister Micheal Martin called the diversion "appalling, reckless and unacceptable."
The incident also has implications for the country's EU funds. A 3-billion-euro (3.7-billion-dollar) EU investment and economic package planned for Belarus is frozen until the country "turns democratic," von der Leyen said.
The EU member states also called on the International Civil Aviation Organization to "urgently investigate" the incident.
Belarus: 'Open to investigation'
Prior to the EU leaders' meeting, Belarus said it is open to an international investigation into the forced landing. Foreign Ministry spokesperson Anatoly Glass rejected EU criticism, and said that Minsk had fully complied with international regulations.
But German Chancellor Angela Merkel said all of Minsk's explanations for the manoeuvre so far had been "totally unbelievable."
Belarus has seen months of protests - matched by a dogged crackdown - after authoritarian President Alexander Lukashenko claimed victory in an election in August last year that the opposition sees as rigged.
Since the poll, which the EU maintains was neither free nor fair, the bloc has imposed sanctions over several rounds for human rights breaches. The total of targeted individuals is currently 88, including Lukashenko himself, plus seven entities.
The 66-year-old has led Belarus - a former Soviet republic in Eastern Europe bordering EU states Poland, Lithuania and Latvia - for more than a quarter of a century, tolerating little dissent.
Minsk has grown closer to Moscow in recent years. But Lukashenko has also maintained relations with EU partners in his almost 27 years in power.
Having agreed on their stance towards Belarus, the EU leaders are set to discuss other foreign relations, such as their strategy towards Russia, throughout the evening.