The Government has announced it is to act "as soon as practicable" to close a loophole that currently allows viewers to watch BBC TV legally without paying the licence fee.

In a keynote speech at the Oxford Media Convention, culture secretary John Whittingdale pledged to stop giving a "free ride" to those who only watch BBC iPlayer on catch-up, arguing that when the licence fee was invented "video on demand did not exist".

At the moment you only need a TV licence if you watch or record TV as it's being broadcast – if you only watch catch-up, you don't need a TV licence. See full details in our Do I need a TV licence? guide.

The new requirement to have a TV licence would only apply to those watching BBC iPlayer on catch-up, and not other catch-up services such as the ITV Hub and Channel 4's On Demand, the Department for Culture, Media and Sport has confirmed.

Speaking at the convention, Mr Whittingdale said: "I will be bringing forward, as soon as practicable, secondary legislation which will extend the current TV licensing regime not only to cover those watching the BBC live, but also those watching the BBC on catch-up through the iPlayer.

"When the licence fee was invented, video on demand did not exist.

"And while the definition of television in the legislation covers live streaming, it does not require viewers to have a licence if they watch BBC programmes through the iPlayer even if it is just a few minutes after transmission.

"The BBC works on the basis that all who watch it pay for it. Giving a free ride to those who enjoy Sherlock or Bake Off an hour, a day or a week after they are broadcast was never intended and is wrong."

Mr Whittingdale says there would have to be an order drafted and agreed by Parliament on the licensing change that he would try to get "passed as soon as we can".

Talking after his keynote speech, he said: "It could be this session if I can get it done and get a slot."

First step towards a BBC subscription?

Martin Lewis, founder of MoneySavingExpert.com, says: "This is the first time there has been a differentiation between the BBC and other networks. We've seen a massive move towards people watching TV online only, to avoid the subscription fee.

"The break-up is quite significant as it could be the first step towards a BBC subscription."

Additional reporting by the Press Association.