A child protection whistleblower has demanded an apology from Kingston Council after leader Derek Osbourne criticised her.

Olivia Butler, former interim head of children’s services, claimed last week there had been a “cover-up” of failures by social workers to help 37-year-old Charito Cruz before her murder.

Speaking to the Surrey Comet, Ms Butler said: “I think they are trying to cast doubt on my credibility by quoting selectively and without context from private correspondence about the circumstances of my departure, obfuscating the fact of my resignation.”

In a prepared statement read out at a council meeting on Tuesday, Coun Osbourne said: “I am not satisfied the representation of events she is now making is consistent with the record we have.”

He said the former director of children’s services Duncan Clark, “had concerns about the guidance and support she was providing to staff and the state of the preparations for the anticipated Ofsted inspection”.

Chief executive Bruce McDonald said: “Allegations made by Olivia Butler 16 months after the tragic death of Charito Cruz are extremely serious and need thorough investigation.

“As soon as the BBC aired its report – the first time I had heard these allegations – I asked Olivia Butler to disclose the basis for her claims.

“The council will investigate whatever information it receives and take any necessary action.”

Mr McDonald said the domestic homicide review, first revealed by the Surrey Comet in December 2012, would take another six months to complete.

Meanwhile lead councillor for children’s services Patricia Bamford has admitted it “crossed her mind” to resign in the wake of the Charito Cruz safeguarding revelations.

The Liberal Democrat councillor said she had been persuaded to carry on by the borough’s director of children’s services, Nick Whitfield.

Opposition Conservative councillors and Kingston Labour Party have called for both Coun Bamford and council leader Derek Osbourne to quit after it was revealed Ms Cruz’s baby daughter had been referred to social services twice before her murder in 2011.

She said: “It is easy to throw arrows from the outside, but it is much harder to take responsibility.

“It is about getting on and doing the job. We have already made significant improvements to the service, and I think it would be counter productive for me to go and have somebody new who wouldn’t know all the issues try and resolve them.”