Cambridgeshire Liberal Democrat Leader, Fiona Whelan has decided reluctantly to stand down following health problems.
Councillor Whelan, who has led the group for the last year, suffered a slip disc in her back just after Christmas and has been in constant pain.
Now, facing a possible operation in the near future, she has decided to step down to give herself time to recover.
Members have appointed their Highways and Transport Spokesman, Kilian Bourke as the group's new leader. He will take over from Cllr Whelan on June 17.
Cllr Whelan said: "I am disappointed at having to step down after only one term of office; but I have struggled with severe pain and found just getting about extremely difficult.
"I am confident in handing over the leadership to Councillor Bourke. He is a very experienced councillor and politician who has worked extremely hard both in his Cambridge ward and for the county council as a whole. I wish him every success."
Cllr Bourke said: "Fiona has been an excellent leader and I am honoured to follow in her footsteps. I look forward to continuing the group's role as a powerful and effective opposition, challenging decisions made by the Conservative administration and ensuring that we do the best for the people of Cambridgeshire at every opportunity."
"This isn't going to be easy given the new Conservative Leadership's disregard for democratic accountability, but that makes the need for effective opposition even greater."
"We will continue to oppose cuts to local services that go way beyond what the government says is necessary. These risk reinforcing the glaring inequalities in wellbeing and achievement that plague Cambridgeshire; this cannot be allowed to happen."
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