Belarus has joined Russia in its attack on Ukraine has become the second country to invade them, the Ukrainian government claims.
A tweet from the official Twitter account of the Ukrainian parliament claimed that troops "have entered" the region of Chernihiv in northern Ukraine.
The claims have been supported by Latvian Defence Minister Dr Atis Pabriks, who also said Belarusian troops had crossed the border into Ukraine, the Mirror reports.
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He told the Commons Foreign Affairs Committee: "This basically means we have two aggressive [nations] at this moment officially.
"I am very much concerned that Russian troops, following orders from the top, will go into the mode similar to that President Assad was using against his population."
The report comes only hours after Belarusian president Aleksandr Lukashenko stated he had no plans to join Putin's war, despite being a supporter.
On Tuesday, he denied that Russian troops were attacking Ukraine via Belarusian territory.
The Tweet from the official @verkhovna_rada Twitter account for the parliament of Ukraine, said: "Belarusian troops have entered Chernihiv region.
"The information was confirmed to the public by Vitaliy Kyrylov, spokesman for the North Territorial Defence Forces.”
The claims mean that Lukashenko has joined Putin in attacking Ukraine on the sixth day of the invasion while Russia continues to try and secure key Ukrainian cities.
Local reports claim that a column of 33 tanks rolled past residents of Slabyn, Pakil and Mykhailo-Kotsyunynsky at 11.30am local time - all these regions are close to Belarus and Kyiv.
Reportedly, Lukashenko has said he plans to deploy more troops to the Ukrainian border.
State news agency Belta quoted him as saying: "Those are well trained rapid deployment groups which are ready to stop any provocation and any military action against Belarus."
Previously, a US official stated that Belarus could send in troops to support Russia.
Speaking to The Washington Post on Sunday, they said: “It’s very clear Minsk is now an extension of the Kremlin.”
