France's top court has struck down a ban on social media for under-15s, saying it infringed upon freedom of expression.

The legislation was backed by French lawmakers in July, making it the first European country to block young people from the platforms, after concerns over the harmful effects on children's mental health.

Friday's ruling by the Constitutional Council overrides the ban, which Emmanuel Macron had pledged to introduce in stages starting in September.

Responding to the news, the French president immediately asked Prime Minister Sébastien Lecornu to prepare a new draft that would take into account all the council's points.

After lawmakers voted through the bill last month, Lecornu referred parts of the legislation to the council - a nine-member authority that checks whether a law complies with the constitution - for review.

The Constitutional Councilsaid it had found that Article 1 of the legislation "constitutes an infringement that is neither appropriate, necessary, nor proportionate" to the freedom of expression and communication for under-15s.

The ruling also raised concerns over the law's requirement to provide proof of age to access online services and said it failed to establish "the legal safeguards necessary".

Macron's office said after the ruling that the French government would work "as quickly as possible" to propose a new draft and said the president was determined to see the reform implemented by early 2027.

The original legislation had envisaged that from September all those under-15 would not be able to open accounts, and verification would be required on all new accounts. And from January, this would have applied to all existing accounts.

Opponents have repeatedly questioned the law's viability and raised concerns over privacy, the efficacy of age-verification tools, the risks of young people bypassing them, and how quickly the ban has been designed and brought in.

Australia was the first country to introduce last December a social media ban for those under-16, although it is widely acknowledged that many in the country continue to use the platforms.

Legislation restricting young people's access to social media has been ramping up around Europe in the past few months.

In May, European Commission President Ursula von der Leyen proposed a "social media delay" for children in the EU, saying new legislation could be put forward in months.

In the UK, former British Prime Minister Sir Keir Starmer announced in June that under-16s in the UK will be banned from social media from January 2027. An optional midnight curfew for UK teens aged 16 and 17 was also announced.