The man aged in his 50s developed lung cancer after he was involved in emergency work at the plant between March and December 2011, following the devastating tsunami.

The Japanese government has paid out compensation in four previous cases where workers contracted cancer following the disaster, according to Jiji news agency.

However, this is the first time the government has acknowledged a death related to radiation exposure at the plant, the Mainichi daily reported.

The paper added the man had worked mainly at the Fukushima No. 1 nuclear plant and other atomic power stations nationwide between 1980 and 2015.

Following the disaster, he was in charge of measuring radiation at the plant, and he is said to have worn a full-face mask and protective suit.

He developed lung cancer in February 2016.

The March 2011 tsunami, triggered by a massive undersea quake, killed around 18,000 people and swamped the Fukushima nuclear plant, sending its reactors into meltdown and leading to the world's worst nuclear disaster since Chernobyl.

Tens of thousands of people evacuated their homes. Authorities have been working to rebuild the region, about 240 kilometres (150 miles) north of Tokyo, although areas near the crippled plant remain uninhabitable because of radiation dangers.