Ofcom will be responsible for regulation of harmful online content under new provisions included in the Online Safety Bill.
But a document published by Ofcom today states age verification measures to prevent underage access to pornography won't be enforceable until the end of 2024.
Tim Cairns, Senior Policy Officer at CARE, said: "Ofcom's roadmap proposes that pornography sites will not be properly regulated in the UK until the end of 2024.
"This is completely unacceptable and Ofcom needs to reassess its timeline and parliament needs to intervene to ensure strict deadlines are placed on the face of the Bill to ensure that children are kept safe online.
"It is not as if age verification is a new or novel concept that Ofcom needs to work through.
"The technology exists to implement it and the public strongly support it being brought in.
"Polling commissioned by CARE found 8 in 10 UK adults support age verification for online pornography.
"If Ofcom does not urgently review its timeline, parliament must intervene and ensure strict time limits for implementation and enforcement are placed in the Bill.
"Children have waited far too long for protection online. Ofcom need to show more urgency in protecting the most vulnerable."