Experts commissioned by the operator of a Japanese nuclear plant that faces possible closure because of a suspected active seismic fault say a decision should wait, citing insufficient data.

Tuesday's request came a day before Japan's nuclear watchdog is to rule on the future of the Tsuruga No. 2 reactor in western Japan. The watchdog's own panel said last week that the reactor most likely sits on an active fault and shouldn't restart.

Operator Japan Atomic Power Co. disputes that view. The decision is being closely watched as the pro-nuclear government moves to restart plants suspended since the Fukushima nuclear crisis.

A geologist at New Zealand's GNS Science who led the utility's study, Kelvin Berryman, said neither side has provided enough data to determine whether the fault is still active.