There had been widespread speculation that Mid Bedfordshire MP had been contemplating a move to UKIP.
However, it is understood the Ukip issue did not come up at her meeting with Sir George this afternoon, which was described as "convivial".
Ms Dorries said: "I am delighted. It is long overdue."
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The very mild weather will continue during the rest of today before it turns wet overnight. Tomorrow will be sunnier but also colder.
Police forces across the Anglia region are facing cuts of £47 million in funding from central government.
There's major disruption on trains between Ipswich and Norwich because a signalling fault near Stowmarket.