Child protection expert Mark Williams-Thomas said the Prime Minister should be clear that today's announcement is more about stopping children and young people accessing child abuse images "rather than tackling offenders accessing this material".
However, Mr Williams-Thomas acknowledged on Twitter that it was "a good step forward":
The announcement this morning by the PM that Google will introduce key word filtering & video DNA is a good step forward.
2 key distinctions-PM focus is more abt stopping children/y.people accessing child abuse images . Than tackling offenders accessing material
It is good that children/y.people are a focus - but this is what the PM should be being clear about. Less spin PR more clear strategy
These are dramatic new steps which will make the internet safer and better for children, a leading Internet safety expert writes.
The search engines have stepped up to the plate - their reforms will help remove video child abuse content more quickly and comprehensively.
Former chief of CEOP Jim Gamble said the government must ask whether they are doing enough in the internet safety debate.