Internet service providers are to be asked by the government to tighten up on website pornography to try to combat the early sexualisation of children.

Ministers believe broadband providers should consider automatically blocking sex sites, with individuals being required to opt in to receive them, rather than opt out and use the available computer parental controls.

Ed Vaizey, the communications minister, is to meet internet providers, including BT, Virgin Media and TalkTalk, "in the near future" to discuss changing the way pornography enters private homes, the Department for Business, Innovation and Skills confirmed. The move is designed to protect children from being exposed to pornography on the net.

"This is a very serious matter. I think it is very important that it's the ISPs that some up with solutions to protect children," Vaizey told the Sunday Times.

"I'm hoping they will get their acts together so that we don't have to legislate, but we are keeping an eye on the situation and we will have a new communications bill in the next couple of years."

The action follows the success of moves by most British internet providers to prevent people inadvertently viewing child pornography websites.

Now ministers want to see adult pornography controlled with similar technology, with sites blocked unless people specifically request access to them. Internet providers had said implementing the scheme would be technically difficult and cost too much. However, some now seem willing to implement the scheme voluntarily.

Andrew Heaney, TalkTalk's executive director of strategy and regulation, told the newspaper: "Our objective was not to do what the politicians want us but to do what is right for our customers. If other companies aren't going to do it of their own volition, then maybe they should be leant on."

Virgin Media said that it had already implemented the technology on its mobile service, but said that parents can control what their children see at home and online. A BT spokesman said they had a "clean feed" system to stop access to illegal sites.

In a parliamentary debate last month, Claire Perry, a Conservative MP who has campaigned for tighter controls, said that 60% of nine- to 19-year-olds had found porn online, while only 15% of computer-literate parents knew how to use filters to block access to certain sites.

The MP said six companies – BT, Virgin, Talk Talk, BSkyB, Orange and 02 – streamed the internet to 90% of homes in the UK. Perry called on the government to put pressure on those companies to install default measures to stop children accessing pornography online.