Lucie Blackman had been working as a bar hostess in Tokyo
Prosecutors are to appeal against the acquittal of the man accused of killing British bar hostess Lucie Blackman in Japan, her mother has said.
Joji Obara, 54, was cleared of any involvement in the death of the 21-year-old but was jailed for life for raping nine women, one of whom died.
Miss Blackman's mother, Jane Steare, of Sevenoaks, Kent, said she was pleased with the appeal and fully supported it.
"All I have ever wanted is justice for my darling daughter Lucie," she said.
Mrs Steare said the British Embassy in Tokyo had confirmed that the city's public prosecutor would appeal against Obara's acquittal.
"I believe there are grounds to be optimistic that an appeal will succeed," she added.
Meanwhile, Mrs Steare is involved in a dispute with Tim Blackman, her ex-husband and Miss Blackman's father, over her claims that he could have undermined the prosecution's case against Obara.
She has criticised him for accepting 100 million yen (£450,000) from a friend of the defendant last year.
Mrs Steare said she and Mr Blackman had both received "unequivocal" guidance that accepting condolence money could lead to a more lenient sentence.
"Those who have colluded with Obara's lawyers and taken money from him will have blood on their hands," she said.
But Mr Blackman argued the payment was not "blood money" and said such "offers of condolence" were common in Japan and did not affect the court case.
He told the BBC: "The judge stated in court that all the payments made did not affect the sentence."
Mrs Steare has also released a statement she said was signed by her ex-husband in September 2006, which questioned "key elements of the prosecution's case".
Tim Blackman returned to the UK from Japan on Thursday
It referred to the cause of Lucie Blackman's death being unknown and that Obara's DNA was not found on her body.
But Matt Searle, from the Lucie Blackman Trust, said the aim of the document at the time was "to highlight any discrepancies in the hope that prosecutors would look into the matter further".
Mr Blackman himself said: "My ex-wife was not in court and is making ignorant statements for maximum damage to me.
"I'm afraid to say the lack of justice for us has been the failure of the prosecution team to develop the case adequately."
Lawyers had claimed Obara drugged and raped Miss Blackman before she died, and then chopped up her body and encased her head in concrete.
But a judge at Tokyo District Court ruled there was no firm evidence that he was responsible for her death.