Japan has recounted its islands – and discovered it has 7,000 more than it previously thought.

Digital mapping by the Geospatial Information Authority of Japan (GSI) recently found there to be 14,125 islands in Japanese territory, more than double the figure of 6,852 that has been in official use since a 1987 report by Japan’s Coast Guard.

However, the GSI this week stressed that the new figure reflected advances in surveying technology and the detail of the maps used for the count – it did not change the overall area of land in Japan’s possession.

It said that while there is no international agreement on how to count islands, it used the same size criterion as the previous survey 35 years ago.

That entailed counting all naturally occurring land areas with a circumference of at least 100 meters (330 feet).

The new number does not include any artificially reclaimed land.

The islands surrounding Japan have been at the heart of several territorial disputes.

Japan lays claim to the Russian-held southern Kuril islands, which Tokyo calls the Northern Territories, a dispute that dates to the end of World War II when Soviet troops seized them from Japan.

Japan also says it has a historical claim to the uninhabited Senkaku Islands in the East China Sea, which it currently administers, but China has repeatedly challenged that claim.

Meanwhile, Japan and South Korea remain locked in a more than a 70-year dispute over the sovereignty of a group of islets known as Dokdo by Seoul and Takeshima by Tokyo in the Sea of Japan, which Korea calls the East Sea.