New Zealand is to introduce a bill seeking to ban under-16s from using social media.

Under the latest proposals, platforms including TikTok, Instagram, Snapchat and Facebook, will have to take steps to check users are over 16 and platforms that fail to meet their obligations could face fines of up to 10% of their global revenue.

Prime Minister Christopher Luxon said social media was exposing children to "harmful content, addictive technology and pressures they are not equipped to deal with". But several political parties have said they will vote against the bill.

The move follows a similar ban in Australia, while countries including the UK and Greece are set to introduce restrictions next year.

Luxon said social media was affecting children's family life, mental health, sleep and education.

"We have protections to keep children safe in the real world and we need them in the virtual world too," he said.

New Zealand's government has not outlined which other "high risk" platforms could be impacted.

A statement said that under the Online Safety Bill, which is being introduced to parliament on Monday, social media companies would be required to "take reasonable steps" to check users are over the age of 16 by using methods including existing account information, facial age estimation and digital identity checks.

Platforms regularly used by children would also be required to regularly assess the risks they pose and report on how they are being identified and reduced.

No penalties are proposed for children, parents or caregivers for breaches of the ban, but fines for social media companies could be substantially higher than in Australia, where the maximum penalty is $99m (£51.7m).

It is unclear if the bill will get enough votes to pass however, after both the Act and New Zealand First (NZF) parties - which are coalition partners in the government - said they would oppose it.

David Seymour, New Zealand's deputy prime minister and leader of Act, said the ban would not work.

Foreign affairs minister Winston Peters, who leads the NZF party, said: "We have been concerned with the proposed legislation and the direction and slippery slope that legislation like this will inevitably take our country."

Peters also described a ban introduced in Australia in December as a "colossal failure".

The ban has been difficult for Australia to enforce, and it has been widely acknowledged that many children under the age of 16 have still been able to access and use banned apps.

Earlier this month, France's top court struck down a similar proposed social media ban, saying it infringed upon freedom of expression.