The Japanese government must halt the return of women and children displaced by the March 2011 nuclear disaster back to areas of Fukushima where radiation levels remain high, a U.N. human rights expert said Thursday.

The special rapporteur on hazardous substances, Baskut Tuncak, also criticized in his statement the government's gradual removal of evacuation orders for most of the radioactive areas as well as its plan to lift all orders within the next five years, even for the most contaminated areas.

"The gradual lifting of evacuation orders has created enormous strains on people whose lives have already been affected by the worst nuclear disaster of this century. Many feel they are being forced to return to areas that are unsafe," he said.