HONG KONG — China and Japan celebrated the 35th anniversary of the establishment of diplomatic relations on Saturday with glittering diplomatic receptions and an exchange of congratulatory messages by leaders of the two countries.

While these formalities would have been held in any event, they held special significance this year because of the inauguration of a new prime minister in Japan who is much better disposed toward China than his two predecessors.

Prime Minister Yasuo Fukuda, who was sworn into office Sept. 25, is the son of Takeo Fukuda, who was prime minister when Japan and China signed their peace and friendship treaty in 1978. For that reason alone, he would have been hailed by China as an old friend. But the new prime minister is known as a moderate in foreign affairs who wants solid relations with China and South Korea, in addition to maintaining a strong alliance with the United States.