Beijing, Oct. 10 (AP) -- China on Monday promised closer cooperation with North Korea in a message to the North's leader, Kim Jong Il, marking the 60th anniversary of his ruling communist party.

The telegram from President Hu Jintao said Chinese-North Korean relations were a "precious treasure" that should be developed.

The message was released by the official Xinhua News Agency and read on China's state television news. It didn't mention the North's contentious nuclear program, which Beijing and other governments have been pressing Pyongyang to dismantle.

China's ruling Communist Party "will make continued efforts to promote friendly relations and cooperation" with North Korea, Hu's message said.

Beijing is North Korea's last major ally and is believed to supply a large share of the impoverished country's food and fuel.

China's Vice Premier Wu Yi and Commerce Minister Bo Xilai were in Pyongyang to participate in the anniversary celebrations.

On Sunday, Kim and the Chinese delegation attended the opening ceremony of a glass factory in Pyongyang that was built with aid from Beijing.

Hu's telegram praised Kim's leadership and said stronger ties would help to maintain regional peace and stability.

China hosted international disarmament talks that last month produced an agreement by Pyongyang to give up all nuclear programs in exchange for security guarantees and energy assistance.

However, North Korea has demanded that it be given a nuclear reactor for power generation before it dismantles its atomic projects.