North Korea says a plenary meeting of the ruling Workers' Party Central Committee was convened on Friday, with the country's leader Kim Jong Un in attendance.

The party's newspaper, Rodong Sinmun, reported on Saturday that the committee began deliberating five items on the agenda to "review the work done in the first half of this year." The last plenary meeting was held in December last year.

It said the meeting would "decide a series of important immediate issues arising in maintaining the upturn in the comprehensive development of Korean-style socialism."

Deliberations are expected to continue throughout Saturday.

Kim and Russian President Vladimir Putin signed a new treaty during a summit in Pyongyang on June 19. The treaty pledges mutual military assistance if either of the countries faces aggression and is placed in a state of war.

The focus of the meeting is on what Kim has to say about his country's relations with Russia, its fifth launch of a military spy satellite, as well as growing tensions with the United States and South Korea.