The clip, which opened the BBC charity telethon on Friday night, saw Henry grow impatient with Colin Firth's Oscar-winning portrayal of King George VI as he stammered over his speech. The Sun reports that the British Stammering Association has branded the sketch "deplorable".
The group's Norbert Lieckfeldt added that it was "a gross and disgusting gleefulness at pointing out someone else's misfortune".
The paper claims that more than 100 viewers have complained to the broadcaster, who has insisted that there was "no malicious intent".
Red Nose Day raised more than £74 million for charity, the highest total in its 23-year history.
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