"The United States stands ready to help the Japanese people in this time of great trial," Obama said in a statement. The President said he and the first Lady expressed their deepest condolences to the people of Japan, who have lost loved ones in the earthquake and tsunamis that has already killed at least 60 people.
The toll could go up significantly as reports of damage to buildings in the quake were yet to come.
"The friendship and alliance between our two nations is unshakable, and only strengthens our resolve to stand with the people of Japan as they overcome this tragedy," he said.
The United States will continue to closely monitor tsunamis around Japan and the Pacific going forward, Obama said and asked all US nationals in the affected region to listen to their state and local officials.
"I have instructed FEMA to be ready to assist Hawaii and the rest of the US states and territories that could be affected," he said.
Meanwhile the US State Department in a travel alert urged US nationals to avoid travelling to Japan in the aftermath of a powerful earthquake, measuring 8.9 magnitude. "US citizens should avoid travel to Japan at this time," it said.
Tokyo airports are currently closed; other airports in Japan may be closed or have restricted access. Public transportation, including trains and subways are closed in the Tokyo area, and service has been interrupted in other areas. Many roads have been damaged in the Tokyo area and in northern Japan, it said.
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