The secretive Kim journeyed to China as recently as May, but his visits are usually cloaked in official secrecy until nearly over. This time, however, Xinhua announced the trip — his fourth since May last year.

Kim Jong-il “visited northeastern China starting from Aug. 25 after his Russian tour,” Xinhua said. The report gave no other details of Kim’s journey, and did not say whether he will meet Chinese leaders.

China is isolated North Korea’s main source of economic and diplomatic support, and Kim has been seeking help from regional powers for his isolated nation, which is struggling with economic hardship and food shortfalls.

Beijing has shored up its support for Pyongyang in the past two years, despite regional tension over North Korea’s actions, including nuclear weapon tests in 2006 and 2009 that drew UN sanctions backed by China.

When Kim visited China in May, the two sides vowed that their alliance, “sealed in blood,” would pass on to their successors.

While in Russia, Kim promised to consider suspending nuclear arms tests and production if international talks on Pyongyang’s atomic program resume, a Kremlin spokeswoman said.

The pledge, made at talks with President Dmitry Medvedev, was intended to improve the chances of reviving the six-nation aid-for-disarmament talks that collapsed when North Korea walked out of them in 2008.