The US Ambassador to Japan visited for the first time on Wednesday the Fukushima Daiichi nuclear plant, where a triple meltdown in March 2011 caused the world’s worst nuclear accident since Chernobyl.

Caroline Kennedy was accompanied by the president of Tokyo Electric Power Company (TEPCO), Naomi Hirose.

She observed an ongoing operation to remove more than 1,500 assemblies of spent fuel from a pool in the building of unit 4.

Ambassador Kennedy then visited the control room of unit one, where she was briefed on what occurred during the accident.

In a written statement released by the US embassy, Kennedy said TEPCO and Japan face a daunting task in the cleanup and decommissioning of Fukushima. She also praised the dedication and determination of the workers at the site.

The US ambassador is set to continue her tour of northeastern Japan with a visit on Thursday to an offshore wind farm.