Russian President Vladimir Putin, left, and North Korea's leader Kim Jong-un smile as they walk after the talks in Pyongyang, North Korea, June 19. AP-Yonhap

North Korea said Friday a planned plenary meeting of its ruling Workers' Party will be a "politically important" event, amid speculation on whether it would discuss follow-up measures to implement a new partnership treaty signed with Russia.

North Korea earlier said it will hold a plenary meeting of the party's central committee in late June to review its policy performances in the first half. But the North's state media have yet to report whether it opened the key party meeting.

The Rodong Sinmun, the North's main newspaper, called the planned party meeting a "politically important occasion" to spur North Koreans' march toward the socialist development.

North Korea usually holds a party plenary meeting for a few days in June. But this year's meeting draws more attention due to the possibility that it could discuss detailed measures to expand cooperation with Russia following its signing with Moscow of the treaty of comprehensive strategic partnership.

North Korean leader Kim Jong-un and Russian President Vladimir Putin held a summit in Pyongyang on June 19, and clinched the treaty that calls for providing military assistance to each other without delay if either side comes under an armed attack.

Article 4 of the 23-point treaty could be seen as warranting automatic military intervention in the event of aggression on either country. That would amount to the restoration of a Cold War-era alliance for the first time in 28 years since a mutual defense treaty was scrapped in 1996. (Yonhap)