- Europe migrant crisis
Image source, ReutersImage caption, Thousands of people are stranded in freezing conditions at the Belarusian-Polish border
Belarus's leader has threatened to cut off gas supplies to Europe if sanctions are imposed over an escalating migrant crisis at the country's border.
Thousands of people are at the border with Poland, enduring freezing conditions in the hope of crossing into the European Union.
EU officials have accused Belarus of provoking the crisis to undermine its security, an allegation it denies.
In retaliation, the EU is reportedly planning a fresh package of sanctions.
But on Thursday the country's long-time authoritarian leader Alexander Lukashenko warned: "If they impose additional sanctions on us… we must respond."
"We are heating Europe, and they are threatening us," he said, referring to a Russian gas pipeline that runs through Belarus and into the EU.
"And what if we halt natural gas supplies? Therefore, I would recommend the leadership of Poland, Lithuanians and other empty-headed people to think before speaking," he added.
His comments raised fresh fears amid worsening natural gas shortages and rising prices in Europe.
The EU's economy commissioner Paolo Gentiloni said the bloc "should not be intimidated" by Mr Lukashenko's threats. Exiled Belarusian opposition leader Svetlana Tikhanovskaya, who now lives in Lithuania, accused the president of "bluffing" over his gas ultimatum.
More EU sanctions on Belarus could be introduced as early as Monday. Possible measures include targeting the airport in the capital, Minsk, in an effort to stop international airlines carrying migrants from landing there.
- The lives entangled in the Poland-Belarus crisis
- How Belarus is helping ‘tourists’ break into the EU
- The many routes taken by migrants to Belarus
The EU has accused Belarus of mounting a "hybrid attack" on its territory by encouraging thousands of people to try and cross into Poland.
Image caption, Large groups of migrants are in central Minsk before heading to the Polish border
It claims the country's leadership had enticed them with the false promise of easy entry to the EU as part of an "inhuman, gangster-style approach".
Mr Lukashenko, who won a largely discredited election last year, has repeatedly denied that Belarus is sending people over the border in revenge for existing EU sanctions.
Pipeline's fate is in Moscow's hands
Anastasiia Stognei, BBC Russian, Moscow
It is hard to tell how realistic Alexander Lukashenko's threats are.
On the one hand, he's a leader known for extravagant antics. In August last year, during mass protests opposing his re-election, he was pictured arriving at his Minsk residence by helicopter, wearing a flak jacket and carrying an assault rifle.
At the same time, when Mr Lukashenko says that he won't stop at anything to protect his country's "sovereignty and independence", he might indeed try to implement his threats.
Nonetheless, shutting off the gas transit would be disastrous for Belarus' impoverished economy – though Mr Lukashenko has made economically irrational decisions before.
But it is also a question of international politics. The gas Mr Lukashenko is threatening to shut off is not his – it belongs to Russia. Any decisions about its fate will be taken in Moscow. And the Russian capital is a far more pragmatic place than Minsk.
Mr Lukashenko has no incentives to argue with the Kremlin – after all, his authority is propped up by financial support from Russia.
Judging from what Moscow had said about the future of Nord Stream-2 pipeline, the question of gas supply to Europe can be used for leverage. But that is a question of supply, not of shutting it off altogether.
In other developments on Thursday:
- The UN Security Council will meet later for emergency talks on the crisis
- In a call with Germany's Angela Merkel, Russian President Vladimir Putin urged the EU to start talks with Belarus to resolve the crisis
- Belarus' neighbours – Lithuania, Estonia and Latvia – released a joint statement warning they faced serious security threats at their borders which risked spilling over into the "military domain"
- The EU is reportedly considering sanctions against the Russian state airline Aeroflot for transporting migrants to Belarus, an allegation Aeroflot denies
Meanwhile at the Polish border, stranded migrants threw rocks and attempted to break a razor wire fence.
Poland has been accused of pushing people back across the border into Belarus, contrary to international rules of asylum.
"There's no way to escape," 33-year-old Shwan Kurd told the BBC, who described arriving in Belarus at the start of November.
"Poland won't let us in. We are so hungry. There's no water or food here. There are little children, old men and women," he said.
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The migrants – mostly from the Middle East – are mainly young men but there are also women and children. They are camping in tents just inside Belarus, trapped between Polish guards on one side and Belarusian guards on the other.
There are unconfirmed reports that two people have died on the Belarusian side in recent days. At least seven people have died on the Polish side of the border, many from hypothermia in recent months.
Iraq says it is organising repatriation flights for Iraqi nationals who want to return from Belarus.