Ukrainian law enforcers are collecting a full evidence base for conducting comprehensive forensic examinations on the use of North Korean missiles by Russia to attack Ukraine, Prosecutor General of Ukraine Andriy Kostin has said.

"We are currently collecting more evidence to send them for comprehensive forensic examinations. We want to conduct them as soon as possible and, at the same time, to ensure a high-level standard of evidence," he said in Kyiv on Friday.

The prosecutor general emphasized that once the comprehensive examination is completed, information about it will be published.

Investigation into Russia's war crime starts immediately after documenting the aftermath of a missile strike, he said.

"Then we can united several episodes into one big case," Kostin said.

While commenting on the European Union's plans to impose sanctions on North Korea for the supply of missiles to Russia, he said that the sanction regime should applied to every country and every institution that helps Russia to wage its war of aggression against Ukraine.

"The sanction regime is a very important element of punishment and restriction. Not all sanctions have instant effect, however, it is very important to stay united at the international level in terms of sanctions against those who help Russia to wage this war, and not only for the prevention of future cooperation with Russia, but also for holding governments and institutions back from committing similar crimes in the future […] and for the prevention of other entities against being involved in this dirty business," Kostin said.