The government has asked local authorities and state-run universities not to post maps provided by Google Inc. on their websites because some of them include foreign place names that undermine Japan's territorial claims, sources said Saturday.

In dispute are the South Korean-controlled islets in the Sea of Japan called Takeshima in Japan and Dokdo in the South, the Japan-administered Senkaku Islands in the East China Sea claimed by China as Diaoyu and by Taiwan as Tiaoyutai, and four Russian-held islands off Hokkaido referred to by Japan as the Northern Territories and by Russia as the Southern Kurils.

Japan is involved in disputes over the sovereignty of each of these territories, and is also battling South Korean efforts to have the Sea of Japan renamed the East Sea.

"Some registrations in the electronic maps on the home pages are incompatible with Japan's stance," the government said in notices earlier this year, according to the sources.

Google says it tries to act in accordance with the positions of each state and to provide fair information, while declining to comment on individual cases.

While the government recommends that public organizations use maps compiled by the Geospatial Information Authority of Japan, it is not clear they are complying, since Google's maps are apparently more convenient.