Japanese Prime Minister Junichiro Koizumi has turned down a request by Peruvian President Alejandro Toledo to meet at the Asia-Pacific Economic Cooperation summit in South Korea.
Japanese officials say Mr. Koizumi does not have time.
Relations between the two countries have soured over former Peruvian President Alberto Fujimori's recent return to South America.
Mr. Fujimori, a Japanese citizen, fled to Japan five years ago in the midst of a corruption scandal. He was arrested last week in Chile. If returned to Peru, he faces charges of corruption and of authorizing death squads.
Last week, Peru recalled its ambassador to Japan after a Japanese consular official in Chile visited Mr. Fujimori in jail.
Lima says Tokyo is interfering in Mr. Fujimori's extradition process, but Tokyo insists it is treating him like any other Japanese citizen.
Some information for this report provided by AP and Reuters.