In return, North Korea has received cash, military technology, food and energy commodities to help it overcome international sanctions.

Ukrainian President Volodymyr Zelenskyy says Russia is preparing to receive another 30,000 troops from North Korea, as well as new launchers for ballistic missiles.

"Russia wants to bring in another 30,000 North Korean troops," President Volodymyr Zelensky said in his nightly address on July 25.