UPDATE: After this story was published, the Coalition changed its policy on the default opt-out internet filter. Read more here .

A Liberal National government in Australia would adopt the opt-out UK approach to filtering the internet for all Australians.

The policy comes less than 41 hours before polls open for voting in the federal election where the Coalition is currently expected to win. It is also almost a year after the Labor government abandoned its plans for mandatory internet filtering, and three years after the Coalition announced that it would not support a policy for mandatory internet filtering.

The announcement, buried in an AU$10 million online safety policy published online today (PDF) announces that under a Tony Abbott government, Australians would have "adult content" filters installed on their phone services and fixed internet services unless they opt out.

"We will work with mobile phone companies (such as Telstra, Optus, Vodafone, and their resellers) to develop online safety standards for smartphones and other devices with mobile network connectivity such as tablets, applicable to their use by children in two age groups: Children up to the age of 12 years and teenagers," the policy states.

"As has recently been achieved in the UK, we expect these standards will involve mobile phone operators installing adult content filters on phones which will be switched on as the default unless the customer proves he or she is at least 18 years of age.

"The Coalition will work with internet service providers (which provide fixed-line broadband services to the home) to develop online safety standards for those services, recognising that they are very often accessed by children.

"As has recently been achieved in the UK, we expect these standards will involve the major internet service providers providing home network filters for all new home broadband services, which will be switched on as the default unless the customer specifies otherwise."

Pre-empting the expected criticism of the Coalition's backflip on internet filtering, the party has said that the filtering proposal is about empowering parents.

"This is a very different approach to the discredited compulsory filter proposal championed by the Rudd-Gillard government, which was abandoned as unworkable," the policy states.

"The Coalition's approach aims to empower parents — by giving them the choice of whether or not to operate a filter at home, [and] by establishing the default setting as one which provides maximum protection."

The Coalition has not indicated whether it yet has the support of any of the major ISPs, unlike UK Prime Minister David Cameron, who had secured the support of the UK internet providers before making the announcement.

As expected, the Coalition has indicated that it will introduce a Children's E-Safety Commissioner to seek to remove harmful material from social media platforms.

The Coalition also announced that cyberbullying could potentially become a criminal offence.

More to come.