In a series of tweets, Granholm said: "I just spoke with Ukraine's energy minister about the situation at the Zaphorizhizia nuclear plant. Russian military operations near the plant are reckless and must cease."

 

She added that the Department of Energy "has activated its Nuclear Incident Response Team and is monitoring events in consultation with Department of Defense, Nuclear Regulatory Commission and the White House. We have seen no elevated radiation readings near the facility".

 

Granholm added that the Zaphorizhizia plant's reactors are "protected by robust containment structures and reactors are being safely shut down".

 

The fire erupted earlier in the day on the third, fourth and fifth floor of the plant's training building after Russian troops shelled the complex.

 

The blaze was brought under control at about 6.20 a.m.

 

In the wake of the incident, share prices tumbled in Asia, the BBC reported.

 

Tokyo and Hong Kong faced the steepest falls, with Japan's benchmark Nikkei index 2.5 per cent lower and the Hang Seng in Hong Kong down by 2.6 per cent.

 

Oil prices rose in Asia during morning trade, with Brent crude above $112 a barrel.