Around 20 countries and numerous Pacific islands have been issued Tsunami warning after Japan's massive 8.9 Richter scale earthquakes, the National Weather Service said.

The wide-ranging list includes Russia and Indonesia, Central American countries like Guatemala, El Salvador and Costa Rica and the U.S. state of Hawaii.

Any tsunami would take several hours to travel across 3,800 miles of ocean from Japan to Hawaii.

Chip McCreary of the Pacific Tsunami Warning Center said officials estimated a tsunami could cause wave magnitudes of up to 2 meters above normal sea level, the CNN reported.

This is a very large earthquake. We've evaluated it as about the same size as the earthquake last year in Chile. However, it's much closer to the Hawaiian islands than the Chile earthquake, he said.

The National Weather Service list comprises of Japan, Russia, the Philippines, Indonesia, Papua New Guinea, Australia, Fiji, Mexico, New Zealand, Guatemala, El Salvador, Costa Rica, Nicaragua, Panama, Honduras, Chile, Ecuador, Colombia, Peru and the United States.