"I feel that it is appropriate to take swift action following recent events. It is important that the public has some certainty and reassurance that the city is under the helm of a solid leadership team, as soon as possible.
"I am confident that councillors will respect my decision and the importance of appointing someone to the role whom I feel I am able to work proactively alongside.
"Cr Clark brings with him strong stakeholder connections, significant community support and a desire to cut through red tape to get things done. I feel that we have the same objectives to steer the Council through the next two years and the important issues we currently face.
"I acknowledge the hard work of Cr Biddle as my deputy over the past year and wish her well for her journey forward."
Nobby Clark welcomed his appointment.
"It is great. My role consists only in support of Tim. And I will accompanying him in all the external meetings to give feedback to the council."
He discounted the idea that the role is a pathway to becoming mayor.
"I do not want to be mayor ... ever. I'm just filling in for Toni.
"I think I will bring a lot of different skills for the position and have the extra time to support Tim when he needs."
Last week Biddle said her decision to resign as deputy mayor was not taken lightly and it had taken some time to come to terms with.
"My time at council has been both incredibly fulfilling and, at times, challenging. In the past 12 months, I have experienced difficulties within our council and in my personal life, which has led to my decision to leave."
Shadbolt has the power to appoint his deputy mayor after a law change in 2012 beefed up the power of mayors.
However, back in 2016 there was a standoff in Horowhenua after councillors voted to oust Mayor Michael Feyen's choice as deputy mayor.
In the end Mayor Feyen backed down and accepted the councillors' choice.
Biddle's resignation comes amid a probe into the council by the Department of Internal Affairs, which has raised concerns about "significant conflict".
Biddle was also taken to hospital in August, for an unknown reason, and was the subject of a code of conduct complaint in the same month.
In recent times, questions have also been raised about Shadbolt's performance.
