Christian charity CARE has welcomed amendments to the Online Safety Bill to enhance age verification on porn websites.
The amendments will hold these websites "to a new higher standard on the age verification or age estimation tools they use".
Websites will also have to be "highly effective in establishing whether a user is a child or not", with executives held personally responsible for keeping children safe.
Ofcom is to issue guidance for websites on the new standards and will release periodic reports on compliance and effectiveness of age verification.
The amendments have been welcomed by Christian charity CARE, which has led a long-running campaign for tougher age verification processes on adult websites.
It is calling on the government to go one step further and ensure that there are no loopholes for social media sites.
Ross Hendry, CEO of CARE, said the measures would "make a real difference".
"Most younger children encounter porn by accident. Robust age verification will help prevent their exposure to content that is disturbing and damaging," he said.
"For older children, the impact of porn is evident in the alarming rise of sexual harassment in schools. Tackling this issue requires curbing underage access."
He added, "It is also good to see new reporting requirements on both the effectiveness of age verification and compliance by pornography sites.
"We trust that Ofcom will take its duty to protect vulnerable children as seriously as parents across the country do. Stronger online protections against harmful content are long overdue. We now hope for swift action."
