An international nuclear expert expressed skepticism Thursday about Tokyo Electric Power Co.'s plan to set up an experimental ice wall to ultimately stop radioactive water from escaping from the troubled Fukushima No. 1 nuclear plant.

"I'm not convinced that the freeze wall is the best option," former U.S. Nuclear Regulatory Commission Chairman Dale Klein, who heads a supervisory panel tasked with overseeing the operator's nuclear safety efforts, said in an interview with Kyodo News.

"What I'm concerned about is unintended consequences," Klein said.