Internet providers in the UK will be forced to automatically offer new customers the option of blocking pornographic and violent material, according to a prominent Cabinet minister.

Culture Secretary Jeremy Hunt said this week that he is lining up a clampdown to protect children by obliging internet service providers to make sure all customers have an ‘active choice’ about using parental controls as part of his forthcoming Communications Act.

Mr Hunt said he was taking the action because he wanted ‘services that are safe for my children’.

A recent survey by regulator Ofcom found the number of parents using filtering software had dropped from about 50 per cent to 40 per cent. And the recent Reg Bailey review into the sexualisation of children recommended increased choice for parental controls.

Mr Hunt told the Royal Television Society’s Cambridge Convention on Tuesday: “When it comes to accessing material that can offend taste and decency standards in their own home, we should put consumers firmly in the driving seat.”

According to The Daily Mail, the Government has not ruled out also coming up with a way of getting existing users to make the choice. It is believed that the controls need to be better signposted, as some parents are not aware of them.

Mr Hunt’s proposal comes after it emerged over the summer that some in the Cabinet were backing the idea of an ‘opt-in’ system that would mean users having to choose to view explicit sites.

The system would mean that parents worried about what their children are looking at online would be reassured that inappropriate material is otherwise automatically blocked.

Research suggests as many as one in three under-tens has seen pornography on the web, while four in every five children aged 14 to 16 admit regularly accessing explicit photographs and footage on their home computers.

Only three per cent of pornographic websites require proof-of-age before granting access to sexually explicit material, and two-thirds do not even include any adult-content warnings.

Tory MP Claire Perry, who has led a campaign for a change in the law, said internet firms should ‘share the responsibility’ of protecting children.

‘The best option would be for the British internet service providers to come up with their own opt-in model and we know they can do it – they worked together brilliantly to block access to child abuse websites,’ said the mother of three.

‘But if they won’t act or are moving too slowly, then I really welcome Jeremy Hunt’s commitment to legislating to sort this out.’

Under the proposed system, pornographic sites will be blocked until an adult user specifically requests it.

Another possibility is a movie-type rating system only allowing adult users in the home to view such sites.

Ministers have held private talks with the biggest internet providers to urge them to adopt an opt-in system themselves.