UN inspectors have confirmed they found "clear and convincing evidence" of a sarin nerve gas attack in Syria last month, adding urgency to moves to neutralise the country's stock of chemical weapons.
Only seven countries worldwide have formally admitted stockpiling chemical weapons and all are in the process of destroying them or have completed destruction.
Here is an overview of global arsenals of chemical weapons and progress in the risky and time-consuming process of neutralising them:
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According to the Organisation for the Prohibition of Chemical Weapons, Albania, India, Iraq, Libya, Russia and the United States, along with a country identified by the OPCW only as "a State Party" but widely believed to be South Korea, have declared stockpiles of chemical weapons to the Hague-based organisation that polices the treaty outlawing such weapons.
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The OPCW, which has 189 member states, cannot check countries that are not party to the Chemical Weapons Convention for possible stockpiles. Syria does not belong to the convention but has now said it is joining. Other non-signatories include North Korea, Angola, Egypt and South Sudan. Israel and Myanmar have signed but not ratified the convention.
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Between them, the seven signatory nations have declared 8.67 million chemical weapons-related items including containers and munitions and 71,196 metric tons of toxic chemical agents. Weapons include mustard gas and nerve agents like sarin and VX. Russia and the United States have the biggest stockpiles. The US stockpile reached about 31,500 tons, according to the Army. Russia, by comparison, has said it amassed about 44,000 tons.
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According to the OPCW, 57,740 metric tons, or 81.1 per cent, of the world's declared stockpile of chemical agents have been verifiably destroyed by the end of July. Albania, India and "a third country" - believed to be South Korea - have completed destruction of their declared stockpiles. An OPCW report released earlier this year said the United States had destroyed about 90 per cent of its stockpile, Russia had destroyed 70 per cent of its stockpile and Libya 51 per cent. Iraq is still in discussions with the OPCW about the best way to destroy its stockpile.
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Thirteen OPCW members have also declared a total of 70 chemical weapons production facilities. The organisation says all 70 have been taken out of commission including 43 destroyed altogether and 21 converted to peaceful purposes.
- AP