A lawyer for Tony Nicklinson said he contracted pneumonia and went rapidly downhill after the High Court's decision last week.
Mr Nicklinson told his lawyer that he was "totally devastated."
He died with his family beside him this morning.
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After cool early morning weather bringing mist and fog, there should be a bright afternoon for most parts of the region.
Any early mist and fog will soon clear, with unbroken sunshine through the day for most.
Early wet spells will clear by midnight to leave clear skies overnight.