The former security minister Admiral Lord West has said he is "pleased" David Cameron is taking the issue of Syria to the UN Security Council.
The former head of the Navy said: "In terms of legality I think action would be legal, for a coalition of the willing.
"But how much better to get the UN Security Council. You'd have many more nations then involved with it (so) you could pull in all sorts of other ways to achieve things."
He added: "We need to be very clear on what is our game plan... What at the end is going to make our nation and the globe more secure and ideally help the Syrian people."
The Prime Minister has said 'the world should not stand idly by' after hundreds were killed in apparent chemical attacks in Syria last week.
Any UK military action in Syria would involve submarine-launched cruise missiles rather than air strikes, a military expert has predicted.