By Chris Buckley and Ben Blanchard
BEIJING (Reuters) - China on Monday voiced confidence in the new leader of its impoverished ally North Korea after his father Kim Jong-il died, promising to support Pyongyang as it enters into a uncertain transition.
"We feel incomparably anguished, and offer our deepest condolences to the entire North Korean people," said China's top leaders, in a statement read out on state television's main evening news.
"The Chinese people will always cherish his memory," said their message, which called Kim a "great leader" who was a "close friend of China."
"We are sure that the North Korean people will abide by Comrade Kim Jong-il's will and unify around the Korean Workers' Party, and under the leadership of Comrade Kim Jong-un turn their anguish into strength," it added.
Impoverished and squeezed by international sanctions for conducting a series of nuclear and missile tests from 2006, North Korea has reached out to Moscow and Beijing for help to fill the gap left by the drying up of South Korean and the U.S. economic assistance.
Over the past 18 months, Kim, who in the past rarely travelled abroad, visited China four times and in August made his first trip to Russia in nearly a decade.
"We are convinced that with the shared efforts of the two sides, the friendship between the parties, governments and peoples of China and the North Korea will be strengthened and developed," said the statement. "The Chinese people will always stand beside the North Korean people."
Kim's visits were mainly aimed at winning economic support, and raised speculation he may finally be opening one of the world's most closed economies.
During Kim's China visit in May, the two sides vowed that their alliance, "sealed in blood," would pass on to their successors.
For China, its much smaller and poorer neighbor is both a buffer and a burden.
China sees North Korea as a strategic barrier against the United States and its regional allies. But that barrier comes with an economic and diplomatic price.
As the North's ties with South Korea and much of the outside world have soured, Kim has leaned more on ally Beijing for support, which has cost China both in economic aid and in strains with South Korea and other nations alarmed by North Korea's nuclear weapons development and military brinkmanship.
China has sought to draw North Korea closer with incentives, and bilateral trade hit $3.1 billion in the first seven months of 2011, an 87 percent increase from the same period last year, according to Chinese customs statistics. Growth was propelled by a 169.2 percent jump in the value of Chinese imports.
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 U.N. sanctions backed by China.
(Editing by Jonathan Thatcher)