Two Conservative councillors resigned last night after a full council meeting.
Opposition leaders have been told that Heidi Allen and fellow Marshalswick South councillor Seema Kennedy are to resign after the meeting at St Albans District Council.
Ms Allen was selected in October to fight a safe Tory seat in South Cambs in the next General Election.
While Ms Kennedy has been chosen as the party's prospective parliamentary candidate in South Ribble, Lancashire.
The Conservatives have not yet commented.
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