The future of the independent inquiry into child sex abuse was thrown into doubt last night after Dame Lowell Goddard became the third chairman to resign.
Abuse victims said the inquiry had "descended into farce" and said they felt "betrayed" by her shock resignation. The inquiry, which they had complained was already beset by delays, is now in danger of collapse.
The 67-year-old, who a former high court judge in New Zealand, had faced criticism over the scale of her pay and benefits and also the amount of time she has spent abroad since taking on the role in April last year.
"I announce with regret my decision to resign as chair of the independent inquiry into child sexual abuse, effective from today.
"When I was first approached through the British High Commissioner in Wellington in late 2014, and asked to consider taking up the role, I had to think long and hard about it.
"After carefully discussing the matter with the home secretary and her officials and seeking the counsel of those people in New Zealand whose opinions mattered to me, I decided that I should undertake the role, given my relevant experience and track record in the area.
"It was, however, an incredibly difficult step to take, as it meant relinquishing my career in New Zealand and leaving behind my beloved family.
"The conduct of any public inquiry is not an easy task, let alone one of the magnitude of this. Compounding the many difficulties was its legacy of failure which has been very hard to shake off and with hindsight it would have been better to have started completely afresh.
"While it has been a struggle in many respects, I am confident there have been achievements and some very real gains for victims and survivors of institutional child sexual abuse in getting their voices heard.
"I have nothing but the greatest of respect for the victims and survivors and have particularly enjoyed working with the Victims and Survivors Consultative Panel which I established."
Under Dame Lowell's generous package she had become one of Britain's highest paid public servants with a £360,000 (NZ$658,151) salary, a £110,000 (NZ$201,101) accommodation allowance and regular free return flights to New Zealand for her and her family.
Since taking on the role she had spent more than 70 days overseas, either on holiday or working abroad.
She also admitted in a preliminary hearing last week that she did not have a clear understanding of aspects of English law.
In her first brief statement, she said she was resigning with "immediate effect".
The inquiry has already been beset by delays and the Daily Telegraph recently highlighted concerns that it could take as long as a decade to conclude with the overall cost running into hundreds of millions of pounds.
In recent days a spokesman for the inquiry had refused to respond to repeated questions about whether Dame Lowell's paid for flights would be First or Business Class.
Despite the shock announcement, Home Secretary, Amber Rudd, insisted the inquiry would continue and a new chairman would be appointed.
She said: "I can confirm that Dame Lowell Goddard wrote to me today to offer her resignation as chair of the independent inquiry into child sexual abuse and I have accepted.
"I want to assure everyone with an interest in the inquiry, particularly victims and survivors, that the work of the inquiry will continue without delay and a new chair will be appointed.
"I would like to thank Dame Lowell Goddard for the contribution she has made in setting up the inquiry so that it may continue to go about its vital work."
The inquiry was set up in 2014 amid claims of an establishment cover-up following allegations that a paedophile ring operated in Westminster in the 1980s.
But within weeks of being announced the inquiry looked to be in doubt when two previous chairman stood down over criticism of their links to the establishment.
Baroness Butler-Sloss, who was the first nominee resigned within days after reports were raised over her handling of an earlier inquiry into abuse in the Church of England.
She was replaced by Fiona Woolf, the former Lord Mayor of the City of London, but she stepped down after it emerged that she had links with Lord Brittan, the former Home Secretary, who had faced a number of allegations of child abuse and who was likely to come under the inquiry's scrutiny.
Phil Johnson, spokesman for the Minister & Clergy Sexual Abuse Survivors group, said: "This latest resignation is deeply disappointing and worrying and I fear for the future of the whole inquiry at this moment.
"The inquiry is already massively behind schedule.
"I am very surprised she has resigned. I don't know what the reasons are but I can't imagine it's the criticism in The Telegraph and the Times. It must go deeper than that.
"I am shocked and deeply concerned about the future of the inquiry. She was the third chair. This means pressing the reset button again and I don't know what the public appetite is for that. It is in danger of looking like a farce. We do need an inquiry to get to the truth and this does not help."
Last night, Peter Garsden, a lawyer who represents a number of alleged victims of Lord Janner at the inquiry, said his clients would feel betrayed by Dame Justice Goddard's resignation.
Mr Garsden said: "This is a disaster. This will set everything back. My clients will feel very let down by somebody in a position of authority in whom they had invested their trust.
"I am sure they will see this resignation as a betrayal of trust whether that is true or not. I am sure there are other factors behind this that have influenced her decision that we don't know about. They now have to find a new chairman very, very quickly.
"While I sensed at the Janner hearings a nervousness on her part, I am very very surprised that she has resigned after a little bit of criticism in the media. I can only assume there are external factors we know nothing about."
• 13 Separate historic abuse investigations carried out by the inquiry
• 2,000 Alleged child sex abuse victims who have contacted the inquiry
About | The Goddard Inquiry
Opened: July 2015 Duration: Up to five years Led by: Justice Lowell Goddard - a senior New Zealand judge Remit: To investigate whether institutions and organisations have taken seriously their duty of care to protect children from sexual abuse in England and Wales. These include:
• local authorities • the police • the Crown Prosecution Service • the Immigration Service the BBC • the armed forces • schools • hospitals • children's homes • churches, mosques and other religious organisations • charities and voluntary organisations
She was the first woman of Maori descent to be appointed. She was one of the first women to be appointed Queen's Counsel in 1998 and became Deputy Solicitor-General for New Zealand in 1992.
In 2007, she chaired a year-long inquiry into police handling of child abuse investigations in New Zealand. She is also a UN committee member who has experience of working with victims of sexual assault and has helped establish a new clinic for survivors of sex abuse.