AFP January16,2013,12:00amTWN

The announcement came as Japanese fighter jets were scrambled in response to a Chinese state-owned Y-12 plane flying close to but not inside the islands' airspace, according to Tokyo's defense ministry.

Separately, official Chinese media reported that Beijing's armed forces have been instructed this year to train for battle, while a Tokyo official said U.S. and Japanese fighter jets carried out joint air exercises.

This week's tensions come after Japan's hawkish Shinzo Abe won a landslide election victory following campaign promises to re-invigorate Tokyo's security alliance with Washington and take a more robust line against Beijing.

The dispute over the islands, known as Diaoyu in Beijing and Senkaku by Tokyo, which controls them, has simmered on and off for years but intensified in 2012 when Japan nationalized those it did not already own, triggering anger and demonstrations in China.

China has repeatedly sent maritime surveillance ships to the area and carried out naval exercises, and both Tokyo and Beijing have scrambled fighter jets to the area in recent weeks in a further escalation.

Commentators say Beijing wants to prove that Japan does not have effective control over the chain to draw Tokyo into concessions.

The cartographic survey was part of a program to map China's territorial islands and reefs and safeguard its maritime rights and interests, the official Xinhua news agency said, without saying when it would take place.

It did not make clear whether it would involve activities on land or be purely sea-based, but quoted Zhang Huifeng, of China's National Administration of Surveying, Mapping and Geoinformation, acknowledging there could be difficulties.

There are some difficulties in landing on some islands to survey, and in surveying and mapping the surrounding sea area of the islands, because some countries infringed and occupied these islands of China, he said.

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China to survey disputed E. China Sea islands: Xinhua