The US claims to have evidence Bashar Al Assads forces are mixing deadly sarin gas and plan to use it on their own people.

Syria's foreign ministry has denied any intention of using them.

President Obama warned the Syrian leader that if he makes the "tragic mistake" of using these weapons, there will be consequences and he will be held accountable.

In televised remarks, an unnamed Syrian foreign ministry official said Syria would "never, under any circumstances, use chemical weapons against its own people, if such weapons exist."