Russia is currently occupying about 20% of Ukraine's territory, Ukrainian President Volodymyr Zelenskiy told Luxembourg's parliament in a video address on Thursday.

"We have to defend ourselves against almost the entire Russian army. All combat-ready Russian military formations are involved in this aggression," he said, adding that the front lines of battle stretched across more than 1,000 kilometres (620 miles). (Reporting by Pavel Polityuk, writing by Max Hunder; editing by John Stonestreet)