A spokesman for the legal firm Carter Ruck has told ITV News: 'Lord McAlpine has issued and served proceedings for libel against Sally Bercow and we are representing her.
"He has put in a claim limited to £50,000."
The peer alleges that the Commons Speaker's wife posted a libellous tweet that wrongly linked him to child abuse.
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Very mild for mid February
Five teenagers have been arrested in London on the suspicion of preparation of acts of terrorism.
Goals from Lucas Perez and Theo Walcott ended Sutton United's FA Cup dream on Monday night.