Making the digital world safe for children is an urgent priority, the United Nations said Friday, adding that those responsible for online harm must be held to account.

UN rights chief Volker Turk said states had to force tech giants to embed child safety into their platforms, and said child harm was the direct result of business practices and design choices.

"The digital world that connects children to learning, community, and creativity also exposes them to real risks to their safety, privacy and well-being," Turk said in a statement.

Online harms in those fields "are not innate or inevitable; they result from design choices and business practices that undermine safety, including addictive design features, such as infinite scroll, autoplay, and persistent notifications from apps", he said.

"Enhancing protection of children online is an urgent priority that we need to make sure not only gets done - but that it gets done right."

In December, Australia became the first country to require TikTok, YouTube, Snapchat and other top sites to remove accounts held by under-16s, or face heavy fines.

Indonesia has imposed a similar ban, while several European countries are looking at following suit.

In a submission to Britain's consultation on the issue which ended this week, the Academy of Medical Royal Colleges said doctors were seeing a "wave of radicalised children" from exposure to "hateful, addictive and grossly distressing content".

"Blanket social media bans are not a one-off panacea," said Turk.

"Simply limiting access to platforms that remain unsafe cannot stand as the endpoint in effectively protecting children."

The UN high commissioner for human rights called for tougher measures by governments and tech firms to make online platforms safe places for children, through better design, data protection, regulation, oversight and accountability.

He called for action to ensure that "those responsible for harm can held to account".

Turk said simply focusing on age restrictions would leave unaltered the designs and algorithms that made the platforms unsafe in the first place.

The UN rights chief also said experience so far showed that bans could be easily circumvented and voiced concern that such bans could even end up pushing children to riskier, even less monitored platforms.

The UN rights office produced a set of 10 guidelines entitled "Getting Children's Safety Online Right".

These included ensuring the maximum protection of children's data as a default setting, while the "micro-targeting" of children for commercial purposes, based on a digital record, "should not be permitted".

They said emerging concerns such as restrictions on artificial intelligence chatbot use or addictive design features may warrant age restrictions.

Measures should be subject to independent oversight, with legal consequences that serve as deterrents, the guidelines said.

There should also be access to remedy for children whose rights are violated.

The UN rights office issued the guidelines as multiple countries are considering social media bans for children, while children and social media may feature on the G7 summit agenda next month.

"For too long, social platforms and apps have not met this responsibility by fully understanding the risks that platforms pose, and taking the steps to address those harms," said Peggy Hicks, the UN human rights office's thematic and special procedures director,

"Often they've prioritised their user-based expansion or engagement rather than the well-being of kids," she told a press conference in Geneva.

Hicks said there was no "quick fix" to the problem, but the guidelines should help ensure future measures are grounded in human rights, and children's rights.

She said children themselves must be involved in the process, since they will often recognise the online threats and problems they face before adults do.

Hicks said tech companies faced a choice: "change how their platforms are designed and operated to better protect children's rights and safety or be forced to do so through increasingly restrictive legislation, jury verdicts, and regulatory fines."