Soldiers, weapons and now a missile unit have all been deployed by North Korea in a bid to support Russia in its ongoing war against Ukraine.

It marks the country’s most significant involvement in a conflict since the 1950s.

In light of recent reports, here’s everything we know about the two countries’ growing military ties.

What are the latest reports?

According to an official at Ukraine’s GUR military intelligence agency, a North Korean missile unit that could be equipped with up to 120 ballistic missiles and six launchers for attacks on Ukraine has begun deploying to western Russia.

The official added that the unit comprises around 90 North Korean personnel and is expected to be based ⁠in the Voronezh region of Russia.

Ukrainian President Volodymyr Zelenskiy said in July that Russia wanted to bring in another 30,000 North Korean troops and was preparing facilities in Voronezh to receive them.

Reuters could not independently verify the claims.

Why is North Korea helping Russia?

Russian President Vladimir Putin and North Korean leader Kim signed a comprehensive strategic partnership treaty during Putin’s June 2024 visit to Pyongyang. The pact includes a mutual assistance provision if either country faces external aggression.

North Korea has cast its deployment as assistance to a treaty partner. Kim said in May 2025 that participation in the war was justified as an exercise of North Korea’s sovereign rights in defence ‌of a “brother nation.”

Analysts say Pyongyang stands to gain hard currency, oil and other economic support, as well as access to Russian military technology ​and battlefield experience for its forces and weapons.

North Korean soldiers have gained combat exposure to drones, electronic warfare, artillery coordination and modern battlefield tactics, while ‌its missile and ammunition makers have been able to assess their equipment ⁠in wartime conditions.

How many North Korean troops have been sent?

Ukrainian, U.S. and South Korean assessments initially put the deployment at 10,000 to 12,000 troops in late 2024.

In January 2025, the U.S. deputy ambassador to the United Nations said more than 12,000 North Korean soldiers were in Russia.

Later Ukrainian and South Korean estimates put the ⁠number of troops in Russia’s Kursk region at about 14,000 to 15,000.

The Ukrainian official said ​this ⁠month that around 9,500 North Korean troops remained in Kursk, but were not then directly involved in operations against Ukraine.

Russia and North Korea confirmed in April 2025 that North Korean troops had fought Ukrainian forces in Kursk.

Russia’s top military commander praised their role after Moscow said it had ⁠retaken Kursk territory, while Pyongyang said the deployment was ordered by leader Kim Jong Un.

What other personnel has North Korea said it will provide?

In ​June 2025, Russian ⁠Security Council Secretary Sergei Shoigu said North Korea would send ‌1,000 sappers and 5,000 military construction workers to Kursk to clear mines and help rebuild infrastructure damaged in the fighting.

That same month, South Korean lawmakers, citing a briefing by the National Intelligence Service, said that North Korea appeared to have begun recruiting personnel for an additional deployment to Russia, while continuing to supply Russia ‌with artillery ammunition and missiles in exchange for economic cooperation and technical assistance.

It remains unclear how many ‌engineers, deminers or additional troops have arrived in Russia, or whether they have been used in combat roles.

What weapons has North Korea provided?

North Korea has supplied Russia with millions of artillery and mortar rounds, ballistic missiles, long-range artillery and multiple-launch rocket systems, according to Ukrainian and independent assessments.

A Reuters analysis with the UK-based Open Source Centre found four Russian-flagged cargo ships made 64 voyages to North Korea’s Rajin port between ⁠September 2023 and March 2025, transporting nearly 16,000 containers of ammunition to Russian ports.

Ukrainian officials said North Korea was supplying about half of the munitions Russia needed on the front lines.

Ukraine’s GUR military intelligence agency said that North Korea had delivered 4 million artillery shells from mid-2023, excluding mortar rounds. It said North Korea had supplied 148 KN-23 and KN-24 ballistic missiles by the start of 2025.

What has the international reaction been?

The United States and its allies have said the troop deployments and arms transfers violate ⁠U.N. Security Council resolutions on North Korea.

Pyongyang has been subject to U.N. sanctions since 2006 over its nuclear weapons and ballistic missile programmes. The sanctions prohibit countries from hosting North Korean trainers, advisers or other officials ‌for military, paramilitary or police training.

Washington imposed additional sanctions ​in December 2024 on North Korean and Russian entities connected to Pyongyang’s military and ‌financial support for Moscow. South Korea also blacklisted individuals and entities linked ​to illicit military cooperation between the two countries.

NATO has said Russia’s growing military and economic ties with North Korea, China and Iran pose a threat beyond Europe, extending to the Indo-Pacific and North America.