International Atomic Energy Agency chief Yukiya Amano is recommending some of the contaminated water from Japan's tsunami-hit Fukushima nuclear power plant be released into the ocean.
Japanese authorities have struggled to contain the rapidly accumulating water used to cool the plant's damaged reactors. Some of the hundreds of tanks used to store the radioactive water have already leaked.
Amano said Monday continued storage of the water is not a realistic strategy. He suggested some of the waste water could be released into the nearby Pacific Ocean, once it is properly treated.
"This is not a long-term solution. In order to avoid the potential difficulties, we recommend Japan to consider the option to release the water after treating it properly, ensuring that it satisfies the Japanese standard after consulting with the stakeholders like the local community," said Amano.
An earthquake-triggered tsunami hit the plant three years ago, leading to a meltdown of three nuclear reactors.
Since then, Japanese authorities have suffered a series of embarrassing setbacks in their efforts to clean up the area, including repeated radioactive leaks.
Engineers say it will take at least four decades to complete the dismantling of the plant.