A strong earthquake rattled Taiwan and small islands in the far south of Japan on Monday, official monitoring sites said, prompting a warning for a 1-metre tsunami for the Okinawa island chain.

There were no immediate reports of damage after the quake in either country.

The Japan Meteorological Agency said a 6.8 magnitude hit near Okinawa, saying it was very shallow. It issued a warning for a 1-metre tsunami in small islands that are part of Okinawa after the 10:43 (0143 GMT) quake.

The weather agency said the tsunami could reach Miyakojima, popular with tourists for diving, at around 11:40 (0240 GMT). There was no warning issued for the main Okinawa island, which hosts U.S. military bases.

Taiwan's Central Weather Bureau said the epicenter of the quake was about 75 km (45 miles) off Taiwan's eastern coast at a depth of about 17 km (10 miles).

The U.S. Geological Survey identified a single quake, measuring 6.6, hitting 72 km southeast of Su-ao in Tawain. It put the depth at 28.9 km.

The Pacific Tsunami Warning Center said there was no threat of a tsunami after the quake, which shook offices in the capital, Taipei.