Mayor of London Boris Johnson told LBC 97.3 Radio that those planning Margaret Thatcher funeral demonstrations "could not use the death of an elderly person for a riot or an affray".
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Celebrities lined up to be photographed with the characters, who famously have antennas on their heads and TV screens on their stomachs.
The Olympic champion released a statement after a newspaper alleged his American coach may have broken anti-doping rules.
Storm Ewan gives a wet and windy end to the weekend across many northern and western areas.