Coventry Council has promised a "rapid improvement" in children's services after Ofsted branded the department as "inadequate".
An additional £5.6 million is being invested in the service in light of the report.
George Duggins, the council's cabinet member for children and young people, said the report was not a reflection on hard-working staff but on the ever-increasing workload:
There is no hiding from the fact that the report’s overall findings are disappointing but many of the problems we face, particularly in the front line of children social care, is down to the fact of the unprecedented volume of work which continues to increase.
We have already responded to this challenge by adding another team of social workers and we have funding to add more as part of the additional £5.6 million because as a council safeguarding is one our highest priorities.