The US Navy said it would move the aircraft carrier Ronald Reagan from San Diego to Japan next year so another carrier could come home for maintenance.
The shuffle will allow the navy to keep one carrier deployed in the western Pacific, where tensions have flared in recent months over the disputed Diaoyus Islands in the East China Sea.
"The security environment in [Asia] requires that the US Navy station the most capable ships forward," the navy's Pacific Fleet said on Tuesday. "This posture allows the most rapid response times possible."
The Reagan's home port will be the Yokusuka naval base in Japan, replacing the George Washington, which moves to Virginia for refuelling of its nuclear reactor. A third carrier, the Theodore Roosevelt, which is undergoing maintenance, will be shifted to San Diego where the Carl Vinson is also based.\
The navy has 10 carriers, one of which is usually undergoing maintenance that can take several years to complete.
The Pentagon has said the disputed island chain, known as the Senkaku Islands in Japan, is covered by the US-Japan defence treaty, which requires the US to come to Japan's aid if it is attacked.