North's leader Kim Jong-un (right) greeting Russian President Vladimir Putin (left), who arrived in Pyongyang on Wednesday for a state visit. (KCNA)

Russian President Vladimir Putin and North Korean leader Kim Jong-un began summit talks in Pyongyang on Wednesday, Russian news media reported, amid concerns about deepening military cooperation.

Putin arrived in North Korea early Wednesday morning in his first trip to the reclusive country in 24 years, as Russia, under international sanctions over its war with Ukraine, has been bolstering military and other cooperation with North Korea.

Putin and Kim started their summit talks at the Kumsusan Palace of the Sun, attended by both sides' delegations, according to Russia's Sputnik news agency.

Earlier in the day, an official welcoming ceremony was held at Kim Il Sung Square in central Pyongyang, according to Russia's news reports.

At the summit, the two leaders are widely expected to discuss ways to upgrade their bilateral ties to a new level. Russia's TASS news agency reported Tuesday that Putin ordered the signing of a comprehensive strategic partnership treaty with North Korea.

It marked Putin's first trip to North Korea since July 2000, when he met with then leader Kim Jong-il, the late father of the current leader. It also came nine months after Kim traveled to Russia's Far East in September last year for a summit with Putin.

Since then, the two nations have been bolstering military ties, with the North being accused of supplying Russia with ammunition for use in Moscow's war in Ukraine in exchange for aid and suspected technological assistance for its space program.

Experts said Putin's trip will likely pave the way for the two countries to deepen military cooperation beyond arms transactions while cementing their solidarity against the United States.

Analysts said Kim and Putin are expected to adopt a joint declaration that calls for both sides to elevate the level of military, security and economic cooperation but saw a low possibility of them clinching a treaty akin to a military alliance.

North Korea and the former Soviet Union signed a treaty of friendship and mutual assistance in 1961. The treaty included a provision for so-called automatic military intervention, under which if one side is under an armed attack, the other provides military troops and other aid without hesitation.

North Korea and Russia signed a new treaty of bilateral ties in 2000, but it did not contain such a provision as it centered on cooperation in the economy, science and culture.

Experts said North Korea and Russia are expected to highlight cooperation in the economic sector as any arms deals and military cooperation violate United Nations Security Council resolutions banning Pyongyang's nuclear and missile programs.

In an article published Tuesday by the Rodong Sinmun, the North's main newspaper, Putin vowed to build alternative systems for trade and settlements with North Korea that will not be controlled by the West and jointly resist "illegal and unilateral restrictions" in an apparent reference to international sanctions.

Experts said Russia is expected to assist North Korea's space development program in exchange for Pyongyang's arms supplies, but it is not likely to transfer sensitive weapons technology to Pyongyang.

In late May, North Korea's attempt to launch a military spy satellite ended in failure as a satellite-carrying rocket exploded right after liftoff. In November last year, North Korea successfully placed a spy satellite into orbit, and it has a plan to launch three more such satellites in 2024.

The two leaders could discuss the issue of North Korea's dispatch of its workers at the summit, experts said. The North has a desperate need to earn foreign currency due to international sanctions, while Russia has been facing a labor shortage amid its war with Ukraine. (Yonhap)