Ukraine approaches International Court of Justice; Russia enters Kharkiv

Germany set to increase defence spending in response to 'Putin's war'

Russian military vehicles pushed into Ukraine's second-largest city on Sunday and explosions rocked oil and gas installations on a fourth day of fighting in the biggest assault on a European state since World War Two.

Meanwhile, Ukraine's President Volodymyr Zelenskiy said on Sunday his nation had submitted an application against Russia to the International Court of Justice (ICJ).

"Russia must be held accountable for manipulating the notion of genocide to justify aggression. We request an urgent decision ordering Russia to cease military activity now and expect trials to start next week," Zelenskiy wrote on his Twitter.

Russian soldiers and armoured vehicles were seen