Moscow: A surprising phone call between North Korean leader Kim Jong-un and Russian President Vladimir Putin has sparked speculation about whether the upcoming U.S.-Russia summit will address issues involving North Korea or its leader.

According to Yonhap News Agency, the North Korean and Russian leaders had phone talks Tuesday, during which Kim expressed "full support" for Russia, while Putin briefed Kim on his upcoming meeting with U.S. President Donald Trump. The phone call came just ahead of Putin's summit with Trump, scheduled for Friday in Anchorage, Alaska, primarily to discuss how to end the nearly four-year-long Russia-Ukraine war.

While many predict that the summit may be too focused on pressing issues related to ending the war to leave room for North Korean matters, some suggest it could be a rare opportunity for the two leaders-both keen on exchanges with Kim-to address North Korean issues, albeit remotely. North Korea has been deeply involved in the war, having deployed nearly 14,000 troops on the Russian side since late last year and committed to sending six thousand more to aid rebuilding efforts, all based on its comprehensive strategic partnership treaty signed with Russia last year.

Though details were not disclosed, Kim and Putin might have discussed how Russia plans to handle the cessation of the war with the U.S. during their phone conversation, as it would inevitably involve the ongoing presence of North Korean forces on Russia's Kursk front line, including whether to withdraw the soldiers. Experts say it would be no surprise if Trump raises issues involving North Korea or Kim Jong-un during his upcoming talks with Putin, given his frequent remarks about his interest in resuming dialogue with Kim and Putin's close personal exchanges with him over the past year.

Against this backdrop, a key point of attention for the Putin-Trump summit will be whether the Russian president conveys any message from Kim, particularly on the resumption of dialogue with Washington, such as the conditions for reviving the talks. In a statement last month, Kim Yo-jong, the powerful sister of Kim Jong-un, suggested that North Korea is open to dialogue with the U.S., as long as the goal is not the country's "complete denuclearization."

"While engaging in talks for a ceasefire, which would require detailed discussions, (Trump and Putin) may not have room to address Korean Peninsula issues, including denuclearization, in depth," said Yang Moo-jin, president of the University of North Korean Studies in Seoul. "Still, Putin could take time to address (North Korea's demand) for the disposal of the U.S.' 'hostile' North Korea policy and the lifting of sanctions, out of respect for Pyongyang," he noted.

Having agreed to "make closer contact in the future" during Tuesday's call with Kim, Putin could also speak again with him after his summit with Trump to convey the results, potentially including any reaction from the U.S. president. In that case, Russia is expected to take on a bridging role between Washington and Pyongyang, one that Seoul has often played in the past, experts also warned, voicing concerns over South Korea's potential exclusion from key North Korea-related dialogue.