Michael Adebolajo and Michael Adebowale are due to go on trial on November 18 over the murder of Fusilier Lee Rigby in Woolwich.
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The news was announced on Instagram by director Spike Lee who described him as a "dear friend" and "a great actor".
In a statement the pair said they remained "great friends" and "will continue to support each other".
The comedian has handed over a not-for-profit cafe he opened last year to a charity that helps ex-prisoners and recovering addicts.