If the Mayor of London really has said this, he should think about the implication of his own words:
Palestinians don't have jet fighters, they only have their bodies to use as weapons. In that unfair balance, that's what people use...The same 'unfair balance' applies between the British state and certain citizens of this country not especially well-disposed towards its foreign policy.
Updated at 2.35 PM: See Harry's comment at the bottom of this post.