Starmer has declared that no online platform will get a "free pass" on the issue of children's online safety as he pledged to "crack down on the addictive elements of social media".
Proposals include a measure that will require tech giants to preserve all of the data on a child's phone if they pass away - as campaigned for by the group Jools' Law - as well as consulting on a possible social media ban for under-16s.
The government - who have been accused of "inaction" by opponents - says it will launch a public consultation next month to seek opinions about restricting children's use of AI chatbots and limit infinite 'doomscrolling' features for children.
The Online Safety Act - which became law three years ago - was written prior to the release of AI chatbots such as ChatGPT and the government plans to close loopholes so the tech is included.
Amendments are also set to be made to the Crime and Policing Bill to ensure chatbots protect users from illegal and harmful content.
Other measures being contemplated include preventing children from using virtual private networks (VPNs) to access pornography and amending the law so chatbots are required to protect users from illegal content.
The government says it will create new legal powers so it can take "immediate action" following the consultation which will mean it "can act fast on its findings within months, rather than waiting years for new primary legislation every time technology evolves".
It follows the rows between ministers and X owner Elon Musk earlier this year as the platform's AI chatbot Grok was used to make fake nude images of women.
Ahead of launching the consultation, Starmer said: "The action we took on Grok sent a clear message that no platform gets a free pass.
"Technology is moving really fast, and the law has got to keep up. With my government, Britain will be a leader, not a follower, when it comes to online safety."
In an article published on the website Substack, the Prime Minister explained that - as a parent to two teenagers - he knows that children's access to social media is "something that is front and centre of a lot of parents' minds right now".
He said: "In the past 20+ years, social media has evolved to become something completely different from the simple, stripped-back pages it was in its conception.
"And in that evolution, it has become something that is quietly harming our children,"
