There is a fundamental difference between Japan's nuclear polluted water and regular nuclear liquid discharge, an official from National Nuclear Safety Administration said in an interview with Xinhua News on Sunday.

The official said regular nuclear liquid is "the drainage from the ground surface or the industrial drainage, which contains a trace of radioactive nuclides." Such liquid "will be treated in the most suitable method and discharged after a strict review."

However, Japan's wastewater is the water that was used to cool the damaged reactors and contains multiple radioactive nuclides from the melted-down nuclear reactor core, which are difficult to deal with, the official said.

During the interview, the official reiterated China's concerns about discharging Japan's nuclear polluted water into the ocean.

"China expressed grave concern over Japan's unilateral decision to dump nuclear polluted water into the sea," the official said, adding that China hopes the Japanese government will further conduct in-depth research on various safe disposal methods, timely disclose all related information and consult the interested parties before making any decisions.

According to the official, China will closely follow the development of the situation, strengthen monitoring of the marine radiation environment and ensure the safety of the country's marine ecological environment.