I'm not holding my breath over this as it sounds like another soundbite from Cameron trying to cool down the protests about the level of overseas spending(currently about 12 billion).It looks like a clever compromise but my guess is that little or nothing will come of it.
It looks like a plan, so long as it doesn't muddy the waters and hide any future defence "savings".
There was some wet eyed luvvie, huggy tart on the Today Programme dripping about the effect this would have on Aid workers and their wider causes. BBC News - 'Building an army can be aid too' . The salient points seem to be:
"We think the British public expect [the aid budget] to be spent on hospitals, and not helicopter gunships," said the head of policy at the aid agency Oxfam.
Mr Lawson said: "We are very worried at Oxfam that any money from the aid buget should be used for the military. Aid from Britain is aving lives as we speak and we need to keep it saving lives not spend it on defence."
Little Miss Bleeding-Heart seemed concerned that Johnny Beggingbowl would confuse "defence" money with "aid" money and place aid workers in greater danger. I've found it hard to follow that logic, myself.