North Korea’s Prime Minister Choe Yong Rim is meeting with top Chinese officials including President Hu Jintao and Premier Wen Jiabao for discussions expected to focus on revitalizing the North's moribund economy.
His trip follows the signing earlier this year of agreements on development zones along their border that bind the North ever more closely to China.
At a meeting with Wen on Monday, Choe said ties between the two countries are at a high.
"Now is the best time in our relations. I'm very glad to bring my delegation to China at this time," he said.
"According to the consensus between our leaders, our relationship is getting deeper and deeper." Beijing hopes projects such as the development zones will help stabilize North Korea's economy and prompt Pyongyang to engage peacefully with the region. While North Korea has made tentative steps toward economic reform, leader Kim Jong Il has been loath to relinquish control over the country's 24 million overwhelmingly poor citizens.
China accounts for 57 percent of North Korea's foreign trade, according to South Korea's Unification Ministry. It provides food and fuel and sells the North manufactured goods in return for access to gold and other minerals.
Kim, 69, has visited China several times in recent years as he seeks to hand power to his son Kim Jong Un. During a trip in August, he reportedly suggested that the North could be open to halting nuclear production and testing if international talks on its program resume.
China has sponsored the long-stalled negotiations, which also involve the U.S., Russia, Japan and the two Koreas.
The talks aim to end the North's nuclear weapons program in exchange for economic and diplomatic support.
North Korea is thought to have enough weaponized plutonium for at least six atomic bombs, and is believed to be working toward mounting a nuclear bomb on a long-range missile.
Last year, it unveiled a uranium enrichment facility that could give it a second way to make nuclear weapons.
China and North Korea maintain a highly insular relationship and details of visits by North Korean officials are only revealed after they leave, if ever.
Chinese Foreign Ministry spokesman Hong Lei said only that Choe would also visit China's commercial hub of Shanghai and the wealthy eastern province of Jiangsu.
The visit will further promote "friendly relations and cooperation" between the countries, Hong said at a daily news briefing Monday.
Choe is one of North Korea's highest-ranking officials and has special responsibility for economic management, said Zhang Liangui, a Korea expert at the ruling Communist Party's official training academy in Beijing.
"North Korea's economy has been suffering badly recently so his visit will target ways to boost growth," Zhang said.
Along with shortages of fuel and other crucial inputs for its economy, North Korea has been pounded by heavy rain and tropical storms this year.
American and North Korean officials met in New York in late July to discuss a possible resumption of the nuclear talks. Nuclear envoys of the two Koreas have met twice in recent months, and North Korea said last month that it had accepted a U.S. proposal that they discuss the recovery of remains of American troops killed during the 1950-53 Korean War.
The United States fought alongside South Korea during the war, which ended with an armistice, not a peace treaty.