BEIJING - North Korean leader Kim Jong-il on Wednesday told the visiting Chinese defense minister that his isolated country's friendship with China was unbreakable, even as ties have been tested by the North's nuclear tests.

Relations between China and nuclear-armed North Korea, once described as being as close as lips and teeth, have soured in recent years, especially since Pyongyang held nuclear test blasts in 2006 and again this year in May.

But Kim told Chinese Defense Minister Liang Guanglie in Pyongyang that ties were in fine form, China's official Xinhua news agency reported.

He said the DPRK-China friendship, a treasure inherited from the older generations of the leaders of the two countries, had stood the test of history and was unbreakable, Xinhua said, using the North's official name, the Democratic People's Republic of Korea.

The two counties celebrated a Friendship Year this year, Kim said, extending the hope of continuing to work to strengthen the bilateral ties comprehensively, the report added.

China fought alongside North Korea during the Korean War of 1950-52, and remains a major supplier of aid, food and oil.

Liang has been on a five-day visit to the North since Sunday.

Following from Chinese Premier Wen Jiabao's visit there early in October, the trip is the latest sign that Beijing wants to bolster bilateral ties with Pyongyang, despite the international sanctions aimed at North Korea's nuclear weapons development.

China is opposed to North Korea's atomic weapons ambitions, and responded to the May test by backing sanctions against North Korea authorized by the United Nations Security Council.

Since 2003, China has hosted six-party talks aimed at ending the North's nuclear arms plans in return for aid and energy. Those talks have stalled under complaints from Pyongyang.

Recent conciliatory words from the North, and a scheduled visit by a U.S. envoy next month, have revived some hopes for renewed negotiations.

The talks bring together North and South Korea, China, the United States, Japan and Russia.

(Reporting by Ben Blanchard; Editing by Bill Tarrant)

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