Presumably it was a case of "shit, they wont agree to fund a 10 billion quid piss up for cockneys. Lets just say it will cost 1/4 of that and by the time they find out, we'll have been given a golden goodbye and will be screwing someone else over"
What a waste of money, the cockney barra boys will be rubbing there hands thinking of all the tak they can be selling on the street corners, muggers paradise.