A crew onboard a Russian ship has spotted debris from Japan's tsunami floating 3,000 kilometres out into the Pacific.

It is believed to be the first confirmed sighting of tsunami debris so far out into the ocean.

The Russian ship was sailing near Midway Atoll, 3,000 kilometres east of Japan, when crew sighted the collection of floating debris.

Among the wreckage was a television set, a refrigerator and a small boat registered in Fukushima.

The crew of the Russian ship recovered the boat and is now trying to trace its Japanese owner.

The International Pacific Research Centre in Hawaii says it understands that this is the first confirmed sighting of debris created by the Japan tsunami in March, which followed a major 8.9-magnitude offshore earthquake.