China will bring its maritime law enforcement bodies under a single organisation, a top official said Sunday, with the country embroiled in a bitter row with Japan over disputed islands in the East China Sea.

The State Oceanic Administration, which runs marine surveillance, will take over management of the coastguard from the public security ministry, fisheries patrols from the agriculture ministry, and customs' marine anti-smuggling functions.

The move was intended to "safeguard the country's maritime rights and interests", Ma Kai, secretary general of the State Council, China's cabinet, told the National People's Congress parliament meeting in Beijing, according to a copy of his speech.

"The effectiveness of law enforcement is not high and the ability to defend rights is inadequate," the speech said.

Operational control regarding China's rights will be overseen by the public security ministry, it added.

The move comes as Beijing and Tokyo row over small islands in the East China Sea administered by Japan but claimed by China.

Chinese marine surveillance vessels regularly patrol what Beijing says are its waters around the Diaoyu islands, prompting accusations of territorial incursions by Tokyo, which refers to the outcrops as the Senkakus.

Both sides have scrambled jets to ward off moves by the other and in February Japan alleged a Chinese frigate had locked its weapons-targeting radar on one of its destroyers. Beijing denied the accusation.

Beijing is also at odds with several Southeast Asian countries, including the Philippines, over islands in the South China Sea.

David Goodman, a China expert at the University of Sydney, said the government restructuring was most likely geared at better managing China's policies on the disputes, which have flared in recent months.

"You'd want greater coordination, greater control about what's going on," he said.