Prime Minister Fumio Kishida visited the crippled Fukushima No. 1 nuclear plant Sunday as the government prepares to release treated radioactive water stored at the facility into the sea, despite opposition from fishers and some neighboring countries.

The visit comes before Kishida meets with his ministers Tuesday to discuss when to begin releasing the water. Government sources earlier said the process may start between late August and early September.

The government is in "the final stage" of procedures before deciding on the timing of the water release, Kishida told reporters in Washington on Friday after he attended a trilateral summit with the United States and South Korea.