Japan's nuclear power regulator on Wednesday lifted an operational ban it imposed on Tokyo Electric Power Company (Tepco)'s massive Kashiwazaki-Kariwa power plant two years ago, clearing the path for it to resume a process towards a restart.

Tepco has been eager to bring the world's largest atomic power plant back online to slash operating costs, but a resumption still needs local consent in Niigata prefecture, on the Sea of Japan coast.

With a capacity of 8,212 megawatts (MW), the plant has been offline since around 2011, when the Fukushima disaster prompted the eventual shutdown of all nuclear power plants in Japan at the time.

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Shares in Tepco had risen sharply after the Nuclear Regulation Authority indicated early this month that it would consider lifting the operational ban after conducting an on-site inspection and meeting with the company's president.

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(Production: Irene Wang)