Is it obligatory to repeat Istinja for Wudu if the period between them was two or three hours and nothing happened after the first Istinja?

One who has performed istinja (ablution of private parts) and then wishes to perform wudu (general ablution) is not required to perform istinja again, even if a long time has passed between the istinja and the wudu, as long as nothing necessitating istinja has occurred during that period.