The new head of the independent inquiry into child sexual abuse has defended the embattled probe and insisted it will not be scaled back.
Professor Alexis Jay admitted its scale and scope were a "substantial challenge" but stressed she would not seek to revise nor reduce the terms of reference.
Last month Dame Lowell Goddard became the third chairwoman to quit the inquiry, which has been beset by problems since it was launched in 2014.
Earlier this week Dame Lowell, a New Zealand High Court judge, delivered a critical assessment of the inquiry - saying there was an "inherent problem" in its "sheer scale and size" and calling for a "complete review".
Meanwhile, one survivors' group has said it may pull out of the inquiry because it does not believe it is "truly independent", citing concerns about the involvement of the Home Office.
The sweeping probe has been described as the most ambitious public inquiry ever in England and Wales. It was earmarked to take five years, but there have been suggestions it could run for as long as a decade.
In a letter to the inquiry's core participants, Prof Jay wrote: "Its scale and scope are a substantial challenge, but the panel and I are absolutely committed to delivering results with pace, confidence and clarity."
Prof Jay, who previously led an inquiry into child sexual exploitation in Rotherham, went on: "I would like to reassure any victim or survivor who is concerned that their experience may be excluded from our work that I have no intention of asking the Home Secretary to revise or reduce our terms of reference.
"I am confident that we can adapt our working methods to make our task more manageable and to progress with our work more quickly."
On her second day as chair she ordered an internal review of the inquiry's approach to its investigations.
She said: "My aim is to explore new ways to deliver the inquiry's investigative work while remaining faithful to its terms of reference.
"I will write to you again when the review process has concluded to tell you about any changes that we propose to make and to invite your views."
Prof Jay referred to criticism "that too many of our staff come from the Home Office", saying: "In fact, less than a quarter of our staff are formerly from the Home Office.
"Their duty and loyalty is to the inquiry and not to any government department.
"Regardless of their background, the inquiry staff are bound together by a commitment to make this inquiry a success, drawing on skills and expertise from the public and private sectors."
She said it was an "operational challenge to mount an inquiry of this magnitude", but insisted: "We are making progress."