Lord Tim Bell, the leading PR and advertising figure who was a close adviser to Baroness Thatcher, said she was expected to need several days of recuperation. It could mean she will spend Christmas in hospital, where she has been accompanied by her daughter Carol.
Lord Bell said the former politician had been in some pain earlier in the week and was sent by her doctor to hospital where it was decided the operation was required.
It was a short procedure using what was described as "minimally invasive surgery", he said."She's fine," he added.
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Today's finale to the three-day men's pro event will follow one of the largest amateur sportive cycling events on the British calendar.
White Rose flags and crowds half a dozen deep met the riders as they swept through the towns and villages of North Yorkshire.
Here's Kerrie with your Calendar forecast for the rest of the holiday weekend