Dai Bingguo, who is China's most senior official on foreign policy, made the comments Sunday in a meeting in Beijing with Kim Yong-Il, a visiting top official with North Korea's ruling Korean Workers' Party, AFP reported.
The meeting follows the April 13 launch of what Pyongyang says was a communications satellite, but which the United States has called a disguised ballistic missile test. It said the rocket disintegrated minutes after launch.
The United States and other critics have said the launch violated UN restrictions imposed on North Korea. The UN Security Council strongly condemned it and said it would tighten existing sanctions.
But Dai had warm words for the leadership of Kim Jong-Un, who took the reins of the poor and isolated state after the December death of his father, longtime supreme leader Kim Jong-Il.
Dai told Kim Yong-Il that Beijing would work with Pyongyang to "push friendly and cooperative China-North Korean relations to a new level", a statement released late Sunday by China's foreign ministry said.
"Under the leadership of Korean Workers' Party First Secretary, comrade Kim Jong-Un, the North Korean Party, government and people will certainly make new achievements in the cause of building a strong and prosperous country," Dai was quoting as saying.
China is North Korea's sole major ally and source of economic support. However, it also voiced misgivings over its neighbour's defiant rocket launch.
The State Department said Friday that it had raised with China allegations that Beijing supplied North Korea with technology for its missile program.
The allegations were made last week by US Congressman Mike Turner, who cited an expert as saying a new missile launcher unveiled in a Pyongyang military parade was likely based on a Chinese design.
North Korea has defiantly pledged to follow up the missile launch with further tests.
A South Korean newspaper, quoting government sources in Seoul, reported Saturday that North Korea also may be preparing for its third nuclear test, possibly within two weeks.
China's Communist Party said Kim Yong-Il was still in Beijing on Monday but would provide no details on how long his visit would last.
Source : Afghan Voice Agency (AVA), International Service