The absence of Jang Song-thaek, uncle of North Korean leader Kim Jong-un, at a key national security meeting may be a sign of a renewed power game inside the reclusive communist nation's leadership, a U.S. expert said Sunday.

Jang, vice chairman of the National Defense Commission, did not attend the meeting of top North Korean officials handling security and foreign affairs, in which Kim ordered "substantial and high-profile important state measures," according to Pyongyang's official media.

Kim recently convened the meeting, viewed as North Korea's equivalent of the U.S. National Security Council, to discuss the impact of new U.N. sanctions imposed on his regime for the Dec. 12 rocket launch and Pyongyang's response. The North's media stopped short of specifying the date and venue for the meeting.

"In my judgment, Jang's glaring absence was significant, signaling the emergence of a possible crack in the senior leadership, especially in the relationship between Kim Jong-un and his all-powerful uncle," Alexandre Mansourov, a specialist on North Korea told Yonhap News Agency. He has monitored North Korea issues for decades.

He raised the possibility of divergent approaches between Kim and Jang to the North's international strategy, especially in regard to the issue of a nuclear test and ways to cope with international sanctions.

"As the perceived 'China man in Pyongyang,' Jang may be deliberately staying out of Kim Jong-un's decisions on such a controversial issue as nuclear testing, which is objected by China, in order to preserve 'clean hands' and his good standing in Beijing," he added.

If that is not the case, national security and foreign policy may not be part of Jang's portfolio yet, said Mansourov, who now works at CENTRA Global Access, a strategic consulting firm. He also works as visiting scholar at the U.S.-Korea Institute of Johns Hopkins University in Washington D.C.

Mansourov also suggested the young North Korean leader, just more than a year into power, might have begun to nudge his uncle out of important policy deliberations, he said.

Mansourov, who once studied in Pyongyang, admitted to the lack of information on the country's inner circles and the difficulty of predicting what will happen.

More clues are expected in the coming weeks or months on whether Pyongyang will go ahead with a nuclear test and news of Jang's public activity, he said.

Mansourov said it's also unclear whether the security and foreign policy meeting, chaired by Kim, is an ad hoc group convened only once on a special occasion or a standing decision-making council.

Seven other participants in the session included two top military officials -- Choe Ryong-hae and Hyon Yong-chol -- and Kim Kye-gwan, first vice foreign minister. North Korea's official news agency, KCNA, released several photos of the gathering, along with a written report, on Sunday (Seoul time).

"What is also eye-catching is the absence of such well-known DPRK (North Korea) foreign policy heavyweights as Kim Yong-nam, president of Supreme People's Assembly, Vice Premier Kang Sok-ju and Kim Yang-gon, Workers' Party secretary for South Korea," Mansourov said. (Yonhap News)