Theresa May is personally responsible for the controversies rocking the child abuse inquiry, a survivor has insisted.
Ian McFadyen, who campaigned for the sweeping investigation to be set up, laid the blame for its failings at the door of the Prime Minister.
The stinging criticism came after it emerged Mrs May was aware there were "tensions" between the former chairwoman of the troubled inquiry, Dame Lowell Goddard, and its panel.
Mr McFadyen said Mrs May needed to account for her "failings".
"I take it as a personal slight, having come to London and been assured by Theresa May that this inquiry was going to be fit for our purposes.
"She now admits she knew there were issues ... It was Theresa May who appointed Lowell Goddard and Theresa May who needs to account for her failings. If there were problems, there should have been procedures to deal with them.
"To then pay Goddard £80,000 when she didn't, or couldn't, complete the job is a national disgrace.
"The fault lies at Theresa May's door - at the door of 10 Downing Street," he told The Times.
Mrs May told MPs there had been "stories" circulating about the former chairwoman but said she could not have intervened on the basis of "suspicion, rumour or hearsay".
No 10 confirmed that Mrs May was still home secretary when she heard about the tensions.
A spokeswoman said: "The stories that she heard were just that there were tensions between the chair and the panel."
Mrs May, who set up the inquiry, insisted the Home Office was not officially notified of concerns about the New Zealand high court judge until late July - less than a week before she finally resigned - by which time Mrs May was in Downing Street.
Pressed on the issue at Prime Minister's Questions, Mrs May said: "There were stories around about the inquiry and about individuals related to the inquiry, but the home secretary cannot intervene on the basis of suspicion, rumour or hearsay."
She added that as home secretary, she had been aware many of the abuse survivors believed "people in positions of power" had over the years intervened to "stop them getting justice".
Labour MP Lisa Nandy, who raised the question with Mrs May in the House, said the PM must now needed to explain what exactly she had known.
"Theresa May set up the abuse inquiry and appointed its chair. She was the home secretary in April when serious concerns were raised with her department, and only she had the power to act on them," she said.
"She suggested that she did know of problems but did nothing at all. For this investigation to regain the trust of survivors, the Prime Minister must now come clean about what she knew when, and why she failed to intervene."