There have been calls for Doncaster's elected mayor Martin Winter to resign
A South Yorkshire council at the centre of a government-led inquiry into its child protection record has been ranked one of the worst in the country.
Poor children's services are to blame for Doncaster Council's overall rating, according to the Audit Commission.
It is one of four councils given a one star rating, the lowest the Audit Commission can give.
Mayor Martin Winter said the rating was not a surprise and the council was working to improve its services
Serious case reviews have been ordered into the deaths of seven children in the borough since 2004.
Children's Minister Beverley Hughes ordered an inquiry into child safeguarding services in Doncaster in January.
On Wednesday, former child protection manager Sharon Docherty, said concerns were raised earlier, when senior officers began a radical overhaul of services between 2004 and 2005.
[We] said to each other at the time: unfortunately, as a result of [a new structure] a child will die
Sharon Docherty, former child protection manager, Doncaster
Ms Docherty, who left the council in 2006, told BBC2's Newsnight programme: "When the new structure came out the lines of responsibility, the lines of accountability, the lines of access to support were so fudged so as to be non-existent, certainly as far as frontline workers were concerned."
When asked if she thought this would end up costing lives, she said: "It's actually something colleagues and I said to each other at the time: Unfortunately, as a result of this a child will die."
Doncaster's rating has been published in the Audit Commission's Comprehensive Performance Assessments (CPA) - the annual data for all English single tier and county councils.
In its assessment of Doncaster, the report stated: "Doncaster Council is not improving adequately because it is not serving children and young people well.
"In particular there are serious concerns about the council's role in protecting vulnerable children."
Despite its overall performance rating, the report said that progress had been made in most other priority areas.
It noted the authority was achieving good results for neighbourhoods in reducing crime and improving the environment.
It stated: "Members have taken steps to address issues of poor governance but it is too soon to judge their effectiveness."
Mayor Martin Winter said: "Our CPA is as expected - there is no surprise since the guidance clearly states that regardless of our other scores, the council's overall rating cannot be higher than that for children's services.
"Improving children's services is central to us improving overall and we are rightly concentrating on this area whilst working hard to maintain and sustain the improvements we have made elsewhere."
Haringey, Milton Keynes and Surrey were the other councils to get a one star rating.