The launch of a rocket carrying a backup radar system for a government intelligence gathering was postponed Thursday by bad weather.

The Japan Aerospace Exploration Agency (JAXA) and Mitsubishi Heavy Industries Ltd. said there was a risk of electrical storm clouds at the time the H-IIA rocket was to have blasted off.

Launch had been scheduled for 10:21 a.m. Thursday at Tanegashima Space Center, Kagoshima Prefecture.

They said the launch would have to be rescheduled, and the earliest possible date would be Saturday.

Intelligence satellites monitor the ground for national security purposes and to assist with disaster planning and relief. The information and images they obtain have been designated state secrets under a contentious law enacted last year.