North Korea has sent more than 13,000 shipping containers suspected of carrying arms to Russia since mid-2022 amid deepening bilateral military ties, a lawmaker said Tuesday, citing a military intelligence report.

The North delivered the shipments that could hold more than 6 million 152-millimeter artillery shells through its eastern port of Najin over the roughly two-year period, according to a Defense Intelligence Agency report submitted to Rep. Kang Dae-sik of the ruling People Power Party.

The military has been tracking signs of the North transferring arms to Russia since the outbreak of the war in Ukraine in February 2022.

"To prepare for a prolonged war in Ukraine, Russia has moved to formalize North Korea as a supply base for weapons and ammunition," the agency said.

The latest figure marks a twofold increase since February, when Defense Minister Shin Won-sik told reporters the North had sent about 6,700 containers to Russia.

The agency said South Korea and the United States are jointly monitoring the possibility of North Korean missiles being sent to Russia, citing Russian missiles fired in Ukraine that have shown characteristics of North Korean missiles, according to Kang.

The military suspects the North could have supplied Russia with 122-mm artillery rounds, mobile anti-air missiles and anti-tank missiles, among other weapons.

In return for North Korea's weapons support, Russia is suspected to be providing technological assistance in North Korea's missile and spy satellite programs, the agency said, citing North Korean leader Kim Jong-un's visit to a Russian space port in September where he held a summit with Russian President Vladimir Putin. (Yonhap)