THE HAGUE — The world's chemical watchdog said on Thursday that 90 percent of the global chemical weapons stockpile has been destroyed,The stockpiles included caches containing chemicals needed to make deadly nerve agents like sarin, the Organisation for the Prohibition of Chemical Weapons said.Around 63,000 metric tonnes of declared chemical weapons, mostly from US and Russian arsenals, have now been destroyed OPCW acting spokesman Peter Sawczak told AFP.