Russian Foreign Minister Igor Ivanov on Thursday urged Japan to tone down public criticism over an alleged Russian spy in Japan, saying the two countries should resolve the issue behind closed doors before moving on to repair ties.

Ivanov conveyed Moscow's message during a bilateral meeting here with Foreign Minister Yohei Kono, a Japanese official said.

Both Kono and Ivanov, in New York for the annual general debate at the U.N. General Assembly, agreed that the spy incident should not derail their countries' efforts to resolve the key irritant in bilateral ties -- a long-standing territorial dispute over Russian-held islands off Hokkaido, a Japanese Foreign Ministry spokesman said.

Kono told reporters he raised the spy issue with Ivanov and both of them agreed that the two countries should continue to strive to forward negotiations on the territorial row and conclude a peace treaty by year's end.