British Foreign Secretary Philip Hammond has said that the UK will play a 'leading role' in any coalition effort against Isis.

"I gave a perfect explanation of the government's position in relation to air strikes against the Syrian regime but of course what people are talking about here is the possibility that there may be some action against ISIL in Syria at some point in the future," he said.

"I've said already in parliament, that would be an order of magnitude more difficult than airstrikes in Iraq for all sorts of reasons; military, legal and technical. But we haven't ruled it out. We haven't made a decision yet about how we will best contribute to the coalition effort against ISIL but I have said this morning in the meeting that Britain in clear that it will play a leading role in this coalition."