Ukrainian intelligence suggests Belarus is showing "readiness to maybe participate directly" in Russia's invasion, "in addition to allowing Russians to use their territory as well as letting them cross the border" into Ukraine, a Ukrainian government official told CNN.
A second source close to the Ukrainian government told CNN that in addition to the Ukrainian intel, the Biden administration has also conveyed to Kiev that Belarus is preparing to invade.
The Washington Post first reported that Belarus was preparing to send soldiers into Ukraine, citing a US administration official.
The intelligence comes as talks are set for Monday between Russia and Ukraine near the Belarusian border.
Belarus is an ally of Russia and is being used as a launch point for Russian troops into Ukraine.
Ukrainian President Volodymyr Zelensky's office said Belarus President Aleksander Lukashenko called his Ukrainian counterpart on Sunday.
Lukashenko said last week that Belarusian troops could join the invasion "if it becomes necessary."
"Our troops are not participating in any way in this operation. We're not going to justify ourselves here about our participation or non-participation in this conflict. I repeat once again. Our troops are not there but if it becomes necessary, if Belarus and Russia need them, they will be there," Lukashenko said, CNN reported.