Confirming the development, Ukraine Prime Minister Denys Shmyhal wrote on Twitter that Polish Prime Minister Mateusz Morawiecki, Slovenia's Prime Minister Janez Janša, and Czech Republic's PM Petr Fiala had arrived in the Ukrainian capital on the behalf of the European Union (EU) Council.

Praising the “courage of true friends", the Ukrainian PM said that the leaders would discuss "support of Ukraine and strengthening sanctions against the Russian aggression."

Polish Prime Minister Mateusz Morawiecki said in a tweet: "It is here, in war-torn Kyiv, that history is being made. It is here, that freedom fights against the world of tyranny. It is here that the future of us all hangs in the balance."

"EU supports UA, which can count on the help of its friends - we brought this message to Kyiv today," he added.

Meanwhile, Ukraine presidential adviser Mykhailo Podolyak has said that negotiations with Russian officials "will continue tomorrow."

Podolyak said that "there is certainly room for compromise."

"A very difficult and viscous negotiation process. There are fundamental contradictions. But there is certainly room for compromise. During the break, work in subgroups will be continued," the presidential adviser wrote on Twitter.