NAGOYA, Japan (AFP) - Mission controllers cancelled the planned take-off of the Solar Impulse 2 from Nagoya in central Japan early Wednesday because of weather problems in the Pacific Ocean.

Around 90 minutes after the 2.30am slot they were working towards, project co-founder Bertrand Piccard told pilot Andre Borschberg that take-off for the Hawaii-bound plane had been shelved, delaying their attempt to fly the solar-powered aircraft around the world.

"The flight was cancelled because of the weather around Hawaii. It's a cold front. The priority is the plane's safety and the pilot's safety," project spokeswoman Elke Neumann told reporters in Nagoya.

Speaking on a webcast moments after climbing out of the plane's cockpit, Borschberg admitted he was "terribly disappointed", but conceded it was the right thing to do.

"We were looking to find a way to make it, but I think it is reasonable not to exceed certain limits," he said.

"The weather is so unstable over the Pacific."