Labour: Mistaken about antisemitism?

On 17th February, Ken Livingstone evoked much derision when he stated, live on LBC Radio (link in this excellent Tom Harris article in Daily Telegraph, at 2min 55secs in the audio at foot of page) :

“I’ve spent 45 years mainly on the left of the Labour Party, mixing with other leftists: I’ve never heard anyone say something that was anti-Jewish. Loads of anti-Israel.”

In the Jewish Chronicle, one week later, Jon Lansman (a key Jeremy Corbyn aide) states:

“Racism, including antisemitism, is not new in the Labour movement: it was not until the 1980s that the efforts to eradicate it became serious, and that was thanks in part to Ken Livingstone as leader of the Greater London Council.”

One of them must be mistaken, surely?