From an NPR interview with Jonathan Freedland, columnist for The Guardian on the question of anti-semitism in the Labour Party.

"So I've been really clear that criticism of Israel is completely fine. And as you say, I've dished it out myself and do. So that's not what's being discussed here. Rather, what's being discussed are two things. First is criticism of Israel that comes dressed in the garb of traditional anti-Jewish language or imagery that would be familiar to any anti-Semite long before there even was an Israel, so notions of Jewish conspiracy or Jewish control of the media or Jewish responsibility for all the world's problems and misfortunes. So that's one form.

And then the other is a criticism of Israel's right to exist, which again I think there is a way of arguing that that is completely legitimate. And there was always a tradition of anti-Zionism among Jews too. But nevertheless is framed in such a way that is applying to Israel a standard (ph) that would not and is not applied to any other country. And there too by making this exception of Jews saying they are the only people in the world who are not allowed the right of self-determination, then too there can be a question of whether a line has been crossed. So I think those are the two areas. And in this recent controversy about figures within the Labour Party, it has been both of those that have come up."

NPR