BEIJING - China will conduct routine patrols near the Diaoyu Islands to assert the country's sovereignty and protect fishermen, an official with the Ministry of Agriculture said on Thursday.

The Diaoyu Islands and their affiliated islets have been China's inherent territory since ancient times, and their surrounding waters are China's traditional fishing grounds, according to the ministry.

Data showed that over 1,000 Chinese fishing boats enter the waters of the Diaoyu Islands each year, with their total catch exceeding 150,000 tonnes.

However, increasing harassment from Japanese ships in recent years has severely affected China's fishing activities, triggering widespread protest and condemnation of Japan.

In order to safeguard the interests of China's oceanic fishing industry and ensure safety for Chinese fishermen, the ministry has asked fishery authorities in Zhejiang and Fujian provinces to include areas surrounding the Diaoyu Islands in their regular patrol scopes, the official said.