An unprecedented quantity of online child sexual abuse content is being blocked by tech companies while legislation aimed at tackling such material remains undelivered, the government has been warned.
There are currently 24,649 web addresses containing such images of youngsters, sometimes even babies, on the Internet Watch Foundation (IWF)'s list of blocked pages - a record number.
The dynamic database is updated twice a day, with every URL confirmed to contain images and videos of abuse.
Once blocked, the IWF works with these firms, as well as hotlines and law enforcement, to have the illegal content removed quickly.
The rise in the number of offending pages indicates that while material is being flagged, it is not being taken down swiftly enough at the source.
It comes as the government's Online Safety Bill, which would aim to crack down on such content, remains in limbo almost three years after it formed part of the Conservative Party's general election manifesto.
'No excuse for bill not to go through'
The bill was due to return to parliament earlier this month after being pushed back from July, but was delayed again following the latest Tory leadership crisis, which saw Rishi Sunak installed as prime minister.
Asked for timescale at PMQs on Wednesday, Mr Sunak only said the government looked forward to bringing the bill back before MPs "in due course".
Susie Hargreaves OBE, chief executive of the IWF, told Sky News that the UK had gone from "leading the world to lagging behind" as a result of the delays.
"We are crying out for this regulation to go through," she said.
"It's not good enough any more that it keeps being postponed. It's essential to get this through this year.
"Children are at huge risk, and it's the government's moral responsibility to deliver what they promised."
'Tens of thousands' of online child sex offences
It comes just a week after research by the NSPCC estimated that more than 13,000 online child sex offences were recorded over the summer.
More than 100 grooming offences and other such crimes are likely being registered by police each day while the online safety legislation remains out of sight, the charity said.
The delay is thought to be down to the bill's vague definition of "online harm", as critics suggest it would give the government too much power to dictate internet discourse.
Ms Hargreaves said: "I understand there are concerns around the legal but harmful content, and privacy, but our concerns are around the children and the images they see.
"Everybody, whether industry or NGOs, we are just so desperate for this regulation to come in and know where we stand and put some of these measures in place."
The Department for Digital, Culture, Media and Sport has said it will return legislation to parliament "as soon as possible."