Poland will keep backing Ukraine, Polish prime minister Donald Tusk said after talks with prime minister Rumen Radev, who is on an official visit to Warsaw.

Tusk pointed to Russia's aggressive behaviour and the trouble its attacks near the border are causing Poland. He said Moscow's strikes close to the border are forcing Poland to evacuate border crossing points. He warned that the coming winter could be critical.

Tusk said he was aware of the differences between Poland and Bulgaria, but added that the two countries agree on one thing: the war between Russia and Ukraine must end. "We don't see any will from Russian president Vladimir Putin on this," the Polish prime minister said.

Tusk said the future of Europe belongs to countries like Poland and Bulgaria. He also noted the traditionally good relations between the two nations.