The stunning purge and execution of the North Korean leader's uncle appears to signal that Pyongyang is trying to reduce its over-reliance on China while seeking to break a deadlock in relations with the United States, a Chinese expert said Tuesday.

Jang Song-thaek, the once-powerful uncle and political mentor of North Korean leader Kim Jong-un, was executed on Dec. 12 on charges of attempting to overthrow the Kim dynasty, corruption and other misdeeds. Jang was also accused of selling the North's coal to "a foreign country" at excessively cheap prices.

The execution marked the biggest political upheaval since Kim took power two years ago and raised concerns about North Korea's economic ties with China as Jang had overseen key business projects with Beijing.

Da Zhigang, director of the Institute of Northeast Asian Studies at the Heilongjiang Provincial Academy of Social Sciences, said the dramatic downfall of Jang "mirrors the divergences among the party, the government and the military forces regarding diplomatic policies and further reveals Pyongyang's anxious desire to shake off its over-dependence on China and find a way out of the deadlock with the U.S."

"Jang's fall shows that North Korea has been seeking de-Sinification," Da wrote in an op-ed piece titled "Purge may mean Pyongyang's swerve away from Beijing," which was published by the state-run Global Times.

"If the execution of Jang is interpreted as an acceleration of the de-Sinification process, then it makes sense that Pyongyang is probably seeking what might be loosely called a 'pro-U.S.' strategy," Da said.

"In the North's history, there is plenty of examples of pro-Chinese figures being purged under the pretense of domestic affairs. Jang's death could result in the acceleration of the North re-orienting to the U.S."

Da also warned that North Korea will become more unpredictable in the wake of Jang's downfall.

"It is certain that the fall of Jang, a moderate in foreign policy and an opponent of missile launches and nuclear tests, will facilitate the resurgence of hard-line military factions," Da said.

"In addition, it will also increase the odds of a fourth nuclear test, and the development of nuclear capacities will be given more priority than economic growth."

South Korea and the U.S. have kept a close watch on North Korea amid fears that the North could carry out provocations to try to forge internal unity in the wake of Jang's execution. (Yonhap News)