David Cameron's emergency talks in Downing Street over possible military action against Syria have finished.
The Prime Minister was joined by senior military and security chiefs, including the head of Britain's armed forces, General Sir Nick Houghton, and MI6 chief Sir John Sawers.
The meeting of the National Security Council also saw a number of key Cabinet figures, including Defence Secretary Philip Hammond, Attorney General Dominic Grieve and Deputy Prime Minister Nick Clegg.
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.