I've not seen that report mate, but there clearly is a big north/south divide and it's therefore extremely unfortunate that the one government minister who was really trying his best to try to fix that - George Osborne - is so criticised by those on the left (and sacked before he got chance to see his initiatives through).
But your stat on government spending (in particular) does seem rather dubious to say the least. In fact, no, it must be wrong, or referring to one particular spending area.
The government spends about £800bn a year and of that more than half is spent on Welfare, Health, Education and Defence - just to pick 4. And none of these are London only. So the 95% figure is impossible.
Unless you mean spending on *government* (rather than government spending) - which since parliament and whitehall are in London, would probably make sense.