The Meteorological Agency said it will inform China, Indonesia, Papua New Guinea, the Philippines, Russia, and South Korea when earthquakes stronger than magnitude-6.5 hit nearby and whether tsunami will be generated from the temblor.

The agency will use special communication networks set up by the World Meteorological Organization to let countries know when and where tsunami are likely to hit and how tall they are expected to be, said Akira Nagai of Japan's Meteorological Agency. The program will begin Monday.

The information will supplement less detailed tsunami alerts issued to 26 Pacific Ocean nations by a U.N.-coordinated network based in Hawai'i.

Japan and its neighbors agreed in 1999 to set up such a system, but the Dec. 26 tsunami disaster in the Indian Ocean, which killed more than 170,000 people, has given the project greater urgency.

The Meteorological Agency is also prepared to supply Indian Ocean nations with the same information if requested, but it hasn't been asked to do so, Nagai said.

The step is the latest expansion of Japan's tsunami warning program to cover areas beyond its own islands.

After the Indian Ocean tsunami disaster, the agency started issuing bulletins on earthquakes measuring magnitude 7.0 or above when they occur far away from Japan in order to warn overseas Japanese residents and travelers of threats in their areas.