President Barack Obama says the U.S. has concluded that the Syrian government carried out a large-scale chemical weapons attack against civilians last week.

The U.S. Navy guided-missile destroyer USS Ramage (DDG 61), one of the military craft en route or in position in the eastern Mediterranean ( U.S. Navy via Getty Images)

Obama says the U.S. has examined evidence and doesn't believe the opposition fighting the Syrian government possessed chemical weapons or the means to deliver them.

Obama says he hasn't made a decision about how the U.S. will respond.

The White House says it's planning a possible military response while seeking support from international partners. But the U.S. has not yet presented concrete proof of Syrian government involvement in the attack.

Some lawmakers are calling for Obama to seek congressional approval for a military action.

US Vows Action In Syria Even Without UN Backing

The U.S. says it will take action against the Syrian government for alleged use of chemical weapons even without the backing of allies or the United Nations.

Britain added a hurdle to deliberations about a military strike on Wednesday when it went to the U.N. Security Council with a draft resolution that would authorize the use of military force against Syria. As expected, the five permanent members of the security council failed to reach an agreement as Russia reiterated its objections to international intervention in Syria.

State Department deputy spokeswoman Marie Harf says the U.S. cannot be held up in responding by Russia's intransigence at the United Nations.

Russia says the use of force without a sanction of the U.N. Security Council is a "crude violation" of international law.


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