North Korea on Wednesday recognised two Russian-backed breakaway "people's republics" in eastern Ukraine as independent states, a separatist leader and the North's official news agency said.

The move makes North Korea only the third country after Russia and Syria to recognise the two breakaway entities, the Donetsk (DPR) and Luhansk People's Republics (LPR), in Ukraine's Donbas region.

In a post on his Telegram channel, DPR leader Denis Pushilin said he hoped for "fruitful cooperation" and increased trade with North Korea, an isolated, nuclear-armed state more than 4,000 miles (6,500 km) away.

The DPR's Embassy in Moscow posted a photo on its Telegram channel of a ceremony in which North Korea's ambassador to Moscow, Sin Hong-chol, handed a certificate of recognition to DPR envoy Olga Makeyeva.

North Korea's official KCNA confirmed on Thursday the country's foreign minister Choe Son Hui sent letters to her counterparts in both territories on Wednesday, recognising their independence.

"In the letters, she ... expressed the will to develop the state-to-state relations with those countries in the idea of independence, peace and friendship," KCNA said.

Ukraine immediately severed relations with Pyongyang over the move.

But the recognition was welcomed by some Donetsk residents living in the self-proclaimed "republic".

"Of course I'm happy," said Olga, who declined to give her surname. "Let more recognise us, so that everybody knows we're here."

Anastasia, who also declined to give her surname, told Reuters the more countries that recognise the entities, the less chance Kyiv had of recapturing control of territory seized by the Russian-backed separatists and Russian armed forces. "Step by step we are joining the world stage," she said.

Russia, which has backed the regions since 2014, recognised them on the eve of its invasion of Ukraine in a move condemned by Kyiv and the West as illegal.

Russia justified its decision to launch the war, which it calls a "special military operation", by saying it was protecting Russian speakers who live there from "genocide".

Kyiv and the West have dismissed these assertions as a pretext for waging war and seizing swathes of Ukraine's territory.

North Korea previously expressed support for Russia's annexation of Crimea in 2014.