Obama yet to decide on Syria action
Barack Obama has insisted he is undecided about the prospect of US military action in Syria - but said any action would be "limited", and not involve rank-and-file soldiers.
The US president said the chemical attack which has killed and seriously injured scores in Syria was "a challenge to the world", but said there was an "obligation to maintain the norm" in outlawing the use of chemical weapons.
President Obama was speaking the day after MPs at Westminster voted against sending UK forces to the conflict zone.
Mr Obama said: "I have not made a final decision about various actions that might be taken to help enforce that norm. I have had my military look at a wide range of options.
"We have consulted with allies, we've consulted with Congress, we've been in conversations with all the interested parties.
"In no event are we considering any kind of military action that would involve boots on the ground, a long-term campaign, but we are looking at the possibility of a limited, narrow act that would help make sure that not only Syria but others around the world understand that the international community cares about maintaining this chemical weapon norm."
Ruling out the use of foot soldiers would limit any US involvement to its sea and air-based military.
It currently has four destroyers, each equipped with cruise missiles, in the Mediterranean. The US sixth fleet, with special responsibility in the Mediterranean, has decided to keep the USS Mahan in the region instead of letting it return to its home port in Virginia, while its fifth fleet is anchored off Bahrain in the Gulf, with two of its navy aircraft carriers each listed as carrying up to 70 jets.
The US is also thought to have several nuclear-powered submarines armed with cruise missiles nearby.
The president said: "We're not considering an open-ended, boots on the ground approach. We will consider options that meet the narrow concern around chemical weapons, understanding that there is not going to be a solely military solution to the underlying conflict and tragedy that's taking place in Syria."