Russia now occupies 20% of Ukraine's territory, Zelensky warns

In an address to Luxembourg’s parliament on Thursday, Ukrainian President Volodymyr Zelensky warned that Russia is currently occupying upwards of 20% of Ukraine’s national territory.

Addressing the lawmakers, Zelensky said that nearly 48,260 sq miles is currently under Russian control – including Crimea and parts of eastern Ukraine that Russian separatists took in 2014, the BBC reported.

"We have to defend ourselves against almost the entire Russian army. All combat-ready Russian military formations are involved in this aggression," he warned, adding that the front line extends for more than 620 miles.

Although the Kremlin announced in March that it would “drastically reduce” its military operations around Kyiv and northern Ukraine, Russian forces have seen concentrated their efforts on eastern Ukraine and now appear close to fully capturing the key city of Severodonetsk.

In a daily briefing on Thursday, Britain's Ministry of Defense warned that Russian troops have taken control of "most" of Severodonetsk. If Moscow were to gain control of the city, it could facilitate the taking of Luhansk, one of the two eastern provinces bordering Russia that form the Donbas region, which Russia has essentially claimed as its own.

But as Russia continues to level the city, Zelensky on Wednesday warned that children are especially vulnerable and that 243 have died, 139 are reported missing and 446 have been injured since Russian forces first invaded Ukraine on Feb. 24.

"These are only those we know about," said Zelensky, who was marking International Children's Day. "We do not yet have all the information from the territory that is currently occupied."

Additionally, Zelensky said an estimated 200,000 Ukrainian youth have been transported to Russia against their will – including orphans and children separated from their families.

"This is one of Russia's most heinous war crimes," Zelensky said. "The Russian state disperses these people on its territory, settles our citizens, in particular, in remote regions. The purpose of this criminal policy is not just to steal people, but to make deportees forget about Ukraine and not be able to return."