Porn sites could be blocked to UK users if they don't comply with new legal age checks.
From July 15, anyone trying to access saucy sites will be required to prove that they are over 18.
But it could mean some sites will be blocked altogether if they don't do enough to prevent youngsters accessing restricted material.
The BBFC - which is responsible for regulating films - says that blocking sites completely is one of the approaches it could take.
The controversial move has been introduced to prevent children accessing obscene images.
A statement from the BBFC, The Sun reports, said: "The BBFC will issue preliminary notifications to a non-compliant site before taking any enforcement action against them."
It said if a site doesn't comply, officials will work out the best course of action.
The watchdog continued: "Blocking a site is not the BBFC's objective and it's important that we allow enough time for a non-compliant site to comply.
"Where blocking becomes necessary, this will be carried out in the shortest time possible."
Social media and search engines could be asked to stop linking to sites which do not carry out full checks.
"Adult content is currently far too easy for children to access online," Minister for Digital, Margot James, said in a statement.
"The introduction of mandatory age-verification is a world-first, and we've taken the time to balance privacy concerns with the need to protect children from inappropriate content.
"We want the UK to be the safest place in the world to be online, and these new laws will help us achieve this.”