"Today we mark an important achievement in our ongoing effort to counter the spread of weapons of mass destruction by eliminating Syria's declared chemical weapons stockpile," Xinhua quoted the president as saying in a statement.
He said the most lethal chemical weapons were destroyed several weeks ahead of schedule aboard the US maritime vessel Cape Ray in international waters of the Mediterranean Sea.
"It further advances our collective goal to ensure that the Assad regime cannot use its chemical arsenal against the Syrian people and sends a clear message that the use of these abhorrent weapons has consequences and will not be tolerated by the international community," Obama said.
The Syrian government headed by President Bashar al-Assad agreed to turn over its declared chemical weapons last September, as Washington and some of its allies threatened to launch air strikes in response to Damascus' alleged use of sarin gas in a conflict with the rebel forces.
"Going forward, we will watch closely to see that Syria fulfills its commitment to destroy its remaining declared chemical weapons production facilities," Obama added.