Russia is sending paratroopers to the Belarus-Poland border for war games amid accusations that Moscow is fomenting chaos.
The troops are being sent to Grodno, a region along the Polish border, as Belarus and Poland clash over migrants and whether they should be allowed to travel en masse across the border.
Hundreds of migrants were stuck in a makeshift camp on Friday desperate for food, water, medicines and warmth but were not being allowed across the border and into Poland, a European Union territory.
The US has raised concerns that Russia could be considering an attack on Ukraine, a warning that, in part, led Ukraine to send almost 10,000 personnel and military equipment to its border.
Russia has been accused previously of using border conflicts to increase its influence in former Soviet republics, notably in Ukraine’s Crimea and Georgia’s Abkhazia regions.
It routinely denies involvement in those regions but it helps explain concerns in Ukraine and Poland that something similar is happening.
Russia on Friday dismissed as inflammatory the US assessment that it was considering a strike on Ukraine.
“Such headlines do nothing more than pointlessly and groundlessly fuel tensions. Russia does not pose a threat to anyone," Kremlin spokesman Dmitry Peskov said. "We have repeatedly said that the movement of our armed forces on our territory should not be a cause for concern.”
The EU called the build-up of Russian troops there “worrying”, as the US said Russia could be on the verge of a "serious mistake".
“We don't have clarity into Moscow's intentions, but we do know its playbook,” US Secretary of State Antony Blinken said.
“Our concern is that Russia may make the serious mistake of attempting to rehash what it undertook back in 2014 when it amassed forces along the border, crossed into sovereign Ukrainian territory and did so claiming falsely that it was provoked.”
Back in Belarus, the Russian Defence Ministry said that as part of joint war games Russian paratroopers will parachute from Il-76 transport planes in the Grodno region.
Belarus is ready to call on Russia for assistance if needed, the Tass news agency reported, quoting the Belarus defence minister.
The Belarusian military said the exercise was intended to test the readiness of their rapid response forces as a result of an “increase of military activities near the Belarusian border”.
The drills will involve air defence assets, helicopter gunships and other forces, as troops practise targeting enemy scouts and illegal armed formations.
Russia had already twice sent nuclear capable bombers to fly over Belarus
Hundreds of people are trapped at a makeshift camp on the border that is desperately short of supplies.
“I am very concerned about the thousands of vulnerable people who are stranded in no-man’s land on Belarus’s borders with Poland, Latvia and Lithuania, at the mercy of the weather as winter fast approaches,” said Dr Hans Henri Klug, the World Health Organisation's Europe regional director.
“These refugees and migrants must be treated with the dignity and respect they are entitled to under international law. This includes the right to health. Women and children are sleeping outdoors in the bitter cold. Several people have already died. And Covid-19 cases are rising sharply across the region."
According to the Belarusian State Border Committee, two women at the camp asked for medical help because of hypothermia caused by the cold weather.
Thousands of migrants have flocked to the country’s border with Poland, hoping to get to western Europe.
Many of them are now stranded at the frontier, setting up makeshift camps, as Polish security forces watch them from behind a razor-wire fence.
The EU accuses Belarusian President Alexander Lukashenko of directing migrant flows in retaliation for sanctions on his government over its crackdown on its opponents.
After an emergency meeting at the UN Security Council on Thursday, the US and European delegations condemned "the orchestrated instrumentalisation of human beings whose lives and well-being have been put in danger for political purposes by Belarus".
Turkey agreed with the EU that it would monitor flights headed to Belarus to prevent them from being used to ferry migrants to the Polish border.