Poland on Friday reported that hundreds of migrants had again tried to breach its border with Belarus, as Belarusian President Alexander Lukashenko said it was "absolutely possible" his forces had helped people cross into the EU but denied inviting them.

The West has accused Belarus of artificially creating the crisis by bringing in would-be migrants from abroad and taking them to the border with promises of an easy crossing into the European Union.

Migrants at a Belarusian logistics centre near the country's border with Poland
Migrants at a Belarusian logistics centre near the country's border with Poland BELTA via AFP / Leonid SHCHEGLOV

Belarus has denied the claim, instead criticising the EU for not taking in the migrants.

"We're Slavs. We have hearts. Our troops know the migrants are going to Germany... Maybe someone helped them," Lukashenko told the BBC.

"But I didn't invite them here," he added.

A deserted migrant camp on the Belarusian-Polish border in Belarus' Grodno region
A deserted migrant camp on the Belarusian-Polish border in Belarus' Grodno region BELTA via AFP / Leonid SHCHEGLOV

Polish border guards said there were attempted crossings by two groups on what is the eastern border of the European Union and NATO -- one involving 500 migrants, some of whom threw rocks and tear gas canisters.

The guards said they had detained 45 migrants.

Map showing the border crossing points between Belarus and the three EU countries of Poland, Lithuania and Latvia.
Map showing the border crossing points between Belarus and the three EU countries of Poland, Lithuania and Latvia. AFP / Kenan AUGEARD

However, there were signs of the crisis easing after Belarusian state news agency Belta reported 2,000 migrants had left a makeshift encampment on the freezing border to spend the night in a nearby warehouse.

Belta published photos of the migrants lying on mats in the facility and wrote that "for several it was their first warm night".

Also, hundreds of Iraqis who had failed to cross into the EU from Belarus returned home Thursday on the first repatriation flight organised by Baghdad.

Iraqi migrants preparing to fly home from Minsk airport, Belarus
Iraqi migrants preparing to fly home from Minsk airport, Belarus AFP

According to the Kremlin, Lukashenko and his main ally, Russian President Vladimir Putin, spoke by phone Friday and stressed "the importance of the establishment of cooperation between Minsk and the EU to resolve the problem".

Meanwhile Ukraine, which borders both Belarus and Poland, said it was preparing "systematically and thoroughly" in case the crisis shifted to its territory.

Belarusian state news agency Belta said 2,000 migrants who had been camped out in freezing conditions on the border spent the night in a nearby warehouse
Belarusian state news agency Belta said 2,000 migrants who had been camped out in freezing conditions on the border spent the night in a nearby warehouse BELTA via AFP / Leonid SHCHEGLOV

"We do not exclude the possibility that Russia will decide to purposefully send a large number of illegal migrants through Belarus to our territory," Ukrainian Interior Minister Denys Monastyrsky told parliament.

He said the situation on Ukraine's border was currently under control, but warned that migrants who decide to cross over will be pushed back with any means necessary, including firearms.

Iraqi migrants preparing to fly home from Minsk airport, Belarus
Iraqi migrants preparing to fly home from Minsk airport, Belarus AFP

The Council of Europe human rights commissioner Dunja Mijatovic called the humanitarian situation along the border "alarming" and demanded an end to Poland's controversial returns of migrants to Belarus.

Belta published photos of the migrants lying on mats in the facility and wrote that "for several it was their first warm night"
Belta published photos of the migrants lying on mats in the facility and wrote that "for several it was their first warm night" BELTA via AFP / Leonid SHCHEGLOV

"I have personally listened to the appalling accounts of extreme suffering from desperate people... who spent weeks or even months in squalid and extreme conditions in the cold and wet woods due to these pushbacks," she said in a statement.

"All pushbacks must end immediately."

She also called on Poland to allow rights activists and media "immediate and unimpeded access to all areas along the border".

Belarus said Thursday there were around 7,000 migrants in the ex-Soviet country.

It said it would take responsibility for sending around 5,000 of those migrants home and claimed that the EU would create a "humanitarian corridor" to Germany for around 2,000.

But Germany said it was not true that it would take in 2,000 migrants.

Poland said pressure on the border was continuing, with the defence ministry noting that attempted crossings via the Bug river, including on pontoons, had increased over the last few days.

Polish border guard spokeswoman Anna Michalska said there were fewer overall attempted breaches at the border compared to last month, but the more recent ones "have become more aggressive".

She told AFP about an incident late Thursday involving around 500 migrants.

"People in the largest group... threw rocks and someone also hurled tear gas at Polish officials. At the same time the Belarusian personnel were using lasers to blind them," Michalska said.

She added that four Polish soldiers had sustained injuries.

On Friday, Polish Defence Minister Mariusz Blaszczak tweeted that Warsaw was "happy to accept Estonia's proposal" to send 100 troops to the border.

The EU and US this week announced fresh sanctions on the Belarusian regime, which has crushed political opposition and independent media since a disputed presidential election last year.

US Secretary of State Antony Blinken told reporters that the US could add to sanctions already imposed on Belarus.

Polish media say at least 11 migrants have died since the crisis began over the summer.