Defending world champion Jorge Lorenzo and current championship leader Casey Stoner have confirmed that they will not take part in the Japanese Grand Prix in October. The earthquake and tsunami disaster in the country in March caused the race to be postponed until October 2. However, the Motegi circuit due to host the race lies just over 100km from the damaged Fukushima nuclear plant and both Jorge Lorenzo and Casey Stoner refuse to race there."I will not go and most riders have the same opinion," said Stoner, the 2007 MotoGP world champion. "That's my opinion and I've had it for some time. Not as long as Jorge. I took more time to make my decision, but I will not go there. "That's my decision. I guess it's up to the organisers to figure out what's going to happen. "If a similar thing happened near my home in Australia I wouldn't be going back there. It'd be the same situation." Both Stoner and Lorenzo ride for Japanese teams -- Stoner for Repsol Honda and Lorenzo for Yamaha -- and the Motegi circuit is owned by Honda. Lorenzo, though, says he will not reverse his decision to boycott October's race. "I took this decision not to go to Japan a long time ago," said the Spaniard. "So I am not active in the ongoing discussions about going to Japan because I have already made my decision. "I think if we can help Japan in another way we will, but I think going there is not real support."