Peking — The ''unofficial'' visit to China last week by North Korean leader Kim Il Sung came at a time when Chinese leaders were making clear their concern over tension on the Korean peninsula.
There is no hard evidence linking the North Korean leader's visit to the outbreak of violence in the joint security area at the Korean truce village of Panmunjom.
But in the days immediately after the Nov. 23 incident, Hu Yaobang, general secretary of the Chinese Communist Party, affirmed the Chinese desire to see an easing of tensions and the subject was discussed in Mr. Kim's meetings with the Chinese leaders.
''I see China weighing in very strongly on this,'' said a Western diplomat.
Kim arrived in Peking only three days after the shootout between North Korean and South Korean and United States security guards, precipitated by the defection of a Soviet citizen to the south. The United Nations command described the incident, in which four soldiers were killed, as ''the most serious violation in the joint security area'' at the truce village of Panmunjom since the Korean war ended in 1953.
The visit to China by Kim, who is both head of state and general secretary of North Korea's Workers' Party, was not made public until Nov. 30, two days after his return to North Korea.
During two days of talks, Kim met with senior leader Deng Xiaoping, party secretary Hu, and other top party and government leaders. He did not meet with Premier Zhao Ziyang, who reportedly was out of the capital.
''They discussed international issues of common concern,'' said Wu Xingtang, spokesman for the International Liaison Department of the Central Committee of the Chinese Communist Party, at an unprecedented press conference Friday.
''Of course, the question of the Korean peninsula was touched upon. . . . Nevertheless, it was not the main topic under discussion,'' Mr. Wu said at the first press conference ever held by the International Liaison Department.
''The two sides expressed the hope that tensions on the Korean peninsula will be relieved,'' Wu said.
Since Kim's last official visit to China in September 1982, there have been reports of two other unofficial visits, but these have not been confirmed by the Chinese authorities. East-bloc sources here speculate that there are provisions for annual consultations between the two communist parties. But Chinese party secretary Hu paid a highly publicized official visit to North Korea six months ago. North Korean Premier Kang Song San visited China in August.
The shooting incident brought the postponement of the second round of talks on economic cooperation between North and South Korea, which were due to be held this week. In blaming the South Korean side for the outbreak of fighting, the North Korean government said the talks could be resumed next year if the atmosphere between the two sides improved.
Relations between the North and South had been improving since September, when Pyongyang offered to provide flood relief aid to South Koreans, and Seoul accepted the offer. China has supported the increased contact between the two sides.
''We hope to see the easing of tensions on the Korean peninsula,'' a Chinese official said over the weekend.
North Korea ''sincerely hopes to reduce tensions on the Korean peninsula'' and ''sincerely hopes the North and South will be reunified in a peaceful manner ,'' the official said, seemingly speaking on behalf of China's closest ally.
''They will begin work for this purpose. We in China fully support their proposition,'' he said.
North Korea has proposed a unification scheme under which each side would retain its respective economic and social systems but the two would form a joint government described as a ''democratic confederal republic.''
South Korea has rejected such wholesale reunification as politically impractical, preferring instead to begin cooperation with sports, trade, and other economic exchanges.