The astonishing decade-long ­association between Jeremy Corbyn and a cabal of Holocaust deniers can be revealed today.

An investigation by The Telegraph shows Mr Corbyn was considered to be a “stalwart” supporter of an anti-Israel campaign group Deir Yassin Remembered (DYR) for several years after its organisers were exposed publicly for their extreme anti-Semitic views.

While there is no suggestion Mr Corbyn shares their views, his association raises serious questions about his judgement.