The latest expert jetted in to run Birmingham’s troubled children’s services department has quit before even officially starting in the role.

Bernie McNally , who was social services executive director at Belfast Health and Social Care Trust had been due to take up the post at the beginning of November after a month’s introductory period.

However it has been decided by “mutual consent” she will not continue in the role.

Ms McNally was to be the latest in a long line of officials charged with turning around children’s social care in Birmingham since 2009.

There have been four strategic directors - Tony Howell, Eleanor Brazil, Peter Duxbury and, since last summer, Peter Hay - overseeing the service in that time.

Mr Duxbury left after 15 months in the role.

Lord Norman Warner was appointed by the Government in March this year as a commissioner to help the council turn around the troubled department.

Birmingham City Council said the news of Ms McNally’s withdrawal was “disappointing” as it thought it had appointed “an excellent candidate from a group of first class people who had applied for the post”.

The council statement said: “During the introductory period in October Bernie decided that she was no longer interested in taking up the role, and by mutual agreement will not be proceeding with the appointment.

“Our priority however is to ensure that children are made safe through what we are doing and this is a big collective challenge.

“It’s important to remind ourselves that our most serious staffing challenge is to get the right number of social workers doing great social work with the best team management around them.”

The authority added that the welfare of children in its care was the priority for the council.

It said: “The council remains very clear about the priority of having stable and long term leadership for children’s social care.

“Throughout Bernie’s induction period the interim leadership previously in place over the summer will continue until a permanent appointment is made.”

Eleni Ioannides, a former social services boss from Bury Council, has now been recruited on an interim basis to head the department.

Birmingham’s children’s services have been rated inadequate since 2008.

Serious case reviews followed the deaths of youngsters including Khyra Ishaq in 2008 and Keanu Williams in 2011.

There were 20 investigations over child deaths from 2007 to November 2013, although not all the children were known to social services.