TOKYO, Aug. 22 (Xinhua) -- Despite public concern and raging opposition from both home and abroad, the Japanese government announced Tuesday it has decided to start releasing nuclear-contaminated wastewater from the crippled Fukushima Daiichi Nuclear Power Plant into the ocean on Thursday.

The ocean discharge which could last several decades is expected to commence Thursday, weather and sea conditions permitting, according to the controversial decision announced by Prime Minister Fumio Kishida following a ministerial meeting held on Tuesday morning.

Kishida visited the wastewater treatment facility at the plant on Sunday and met with the head of Japan's national fisheries federation on Monday in hopes of gaining an understanding.

"Our position has not changed, and we continue to be opposed to the ocean discharge," Masanobu Sakamoto, head of the National Federation of Fisheries Cooperative Associations said after the meeting.

Hit by a magnitude-9.0 earthquake and an ensuing tsunami on March 11, 2011, the plant suffered core meltdowns that released radiation, resulting in a level-7 nuclear accident, the highest on the International Nuclear and Radiological Event Scale.

The plant has been generating a massive amount of water tainted with radioactive substances from cooling down the nuclear fuel in the reactor buildings, which are now being stored in about 1,000 storage tanks.

The Fukushima plant has stored more than 1.3 million tons of nuclear-contaminated wastewater, and the discharge is planned to continue for more than 30 years, according to the Tokyo Electric Power Company (TEPCO), the operator of the plant.

In 2015, the Japanese government and TEPCO made an agreement with fisheries cooperative associations of both Fukushima prefecture and the nation that they would not proceed with any wastewater disposal "without the understanding of relevant parties."

"I had a faint hope that they would keep the promise, but eventually that was a lie," a 62-year-old fisherman from Iwaki City in Fukushima Prefecture was quoted by local media as saying.

A total of 88.1 percent surveyed expressed concerns over the government's plan to discharge treated radioactive wastewater into the ocean, as the disapproval rate of the Kishida-led cabinet rose to an eight-month high, according to the latest opinion poll conducted by the national news agency Kyodo. ■