Terry Jones of the Monty Python comedy troupe has been diagnosed with dementia.

A representative for the writer and director told The Telegraph that "Terry has been diagnosed with primary progressive aphasia, a variant of frontotemporal dementia."

The representative added that the illness affects Jones’ ability to communicate and prevented him from giving interviews.

Jones, 74, and the other Pythons organized in 1969 and wrote and performed the television series “Monty Python’s Flying Circus” until 1974.

He co-directed the film “Monty Python and the Holy Grail” with Terry Gilliam, and was sole director on two further Monty Python movies, “Life of Brian” and “Monty Python's The Meaning of Life”, for which he received a BAFTA nomination for Original Song Written for a Film in 1984.