Barack Obama says the Assad regime must face consequences for using chemical weapons - but says no decision has yet been made on the use of force.
In an interview with PBS NewsHour, he says there is no doubt that the Assad regime was responsible for the attacks which killed several hundred people.
His comments come as the UN Security Council continues to discuss a draft resolution which calls for 'all necessary means' to protect Syrian civilians.
President Obama says the use of chemical weapons is not acceptable - and Assad must face consequences.
