Belarus, a Russian ally, is preparing to join the assault on Ukraine, according to government sources.

According to several reports, the country may dispatch special forces to join the combat in Kyiv, escalating the conflict in eastern Europe.

Dictator Alexander Lukashenko has already allowed Russian troops to use his country's border with Ukraine, which is closest to Kyiv. Missiles have also been fired from Belarussian territory.

Ukrainian president Volodymyr Zelensky said on Sunday he had spoken by phone to Lukashenko without revealing any more details.

Earlier he rejected a Russian offer of peace talks because they would be held in Belarus.

Andriy Zagorodnyuk, Ukraine's former defence minister, believes Belarus may get further involved after a direct demand from Vladimir Putin, The Guardian reported.

He told the paper: 'Republic of Belarus is highly likely to join the Russian war against Ukraine. On Russian side. There is an information about airborne troopers from Republic of Belarus loaded on the planes to enter Ukraine.

'This is a terrible development as it involves a country, which until very recently was a great friend of Ukraine; which people always considered Ukraine as a brotherly nation. Ukraine and Belarus has never been to war one with another in their many hundred years of history.'

TOPSHOT - This handout video grab released by the Russian Defence Ministry on February 19, 2022, shows a Russian paratropper during a joint exercise of the armed forces of Russia and Belarus as part of an inspection of the Union State's Response Force, at the Obuz-Lesnovsky firing range near the city of Baranovichi in Belarus. - Belarusian President Alexander Lukashenko, an ally of Moscow, said on February 17, 2022 that his country would be ready to welcome
Belarus has already allowed Russia to use its territory for attacks (Picture: Getty)

Special ops troops were reportedly seen loading up planes for an attack on Kyiv, the Mirror reported, citing a senior Ukrainian source.

Russian troops were joined by the Belarussian army for 'exercises' in a show of strength ahead of the invasion earlier this month.

Lukashenko is currently asking his citizens to vote on constitutional amendments which would allow him to stay in power until 2035.

He cracked down on widespread protests in 2020, which led to him being hit with further sanctions from the west.

BREST REGION, BELARUS - FEBRUARY 19, 2022: A Sukhoi Su-35S fighter jet of the Russian Aerospace Forces takes part in the Allied Resolve 2022 joint military drills held by Belarusian and Russian troops at the Obuz-Lesnovsky training ground. The military exercise is being held from February 10 to 20 as part of the second phase of testing response forces of the Union State of Russia and Belarus. Peter Kovalev/TASS (Photo by Peter Kovalev\\TASS via Getty Images)
Ukraine is fearful of attacks from above (Picture: Getty)

Zelensky has issued a video message rebuking Belarussians for allowing their country to be used as a staging ground for an invasion the likes of which has not been seen since the Second World War.

Back then, both Belarus and Ukraine faced a Nazi invasion as parts of the Soviet Union

But you aren't on the same side with us in the war that is going on now,' Mr Zelensky said in Russian, which is widely spoken in Belarus.

'The Russian military is launching missiles at Ukraine from your territory. From your territory they are killing our children, they are destroying our homes and trying to blow up everything that has been built for decades.'

CORRECTION / This handout video grab taken and released by the Belarussian Defence Ministry on February 19, 2022, shows Russian (L) and Belarus (R) soldiers shaking hands during joint exercises of the armed forces of Russia and Belarus as part of an inspection of the Union State's Response Force, at a firing range near Brest. (Photo by Handout / MINISTRY OF DEFENCE REPUBLIC OF BELARUS / AFP) / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT
Ukraine's leader has questioned how Belarusians can support the attack (Picture: Getty)

In an emotional speech, the Ukrainian leader questioned how Belarusians will be able 'to look into the eyes of your children, into the eyes of each other'.

'We are your neighbours. Be Belarus, not Russia,' he said.

Lukashenko quickly hit back, calling the Ukrainian president an American puppet and claiming that the Russian attack resulted from Zelensky's failure to accept Russian President Vladimir Putin's demand for Ukraine to renounce its bid to join Nato.