The Sun is to start charging for access to its website later this year, News International chief executive Mike Darcey has revealed.
The news came just hours after the Telegraph announced it was to adopt a metered paywall model for its website - charging readers who access more than 20 articles a month.
The two papers are the third and fourth most popular UK national newspaper titles online. The Telegraph attracted 3.1m 'unique browsers' a day in January according to ABC, and The Sun 1.8m.
Darcey revealed the paywall move for The Sun at a drinks reception for journalists who cover the media held at NI's new Wapping headquarters.
Asked whether The Sun would be going behind a paywall, he said: "It's a reasonably safe assumption that we will looking to...iron out inconsistencies" in the online model across NI titles adding thatThe Sun was a "very clear inconsistency".
He said the move would be timed to make the most News International's £20m deal to show near-live clips of Premiership football highlights on its websites which starts in August.
Asked by Press Gazette what he thought about the Telegraph's move to a metered-online paywall, he said: "I'm delighted they are moving in our direction".
He said he would watch the Telegraph experiment with interest and did not rule out following suit if "it looks like it is successful in drawing people in to making them paying customers" without "cannibalising" paid-for readership.
Darcey said that 20 million people a week are still buying a newspaper in the UK and that his experience working for BSkyB had proven to him that it is possible to run a successful paid-for product in an environment where there is high quality free competition.
He said that combined print and digital sales of The Times were "pretty much flat year on year at the minute and there aren't many publications that can say that".
He added: "People make so much of The Times going behind a paywall but it has been behind a paywall since 1875."
Darcey said it was possible to have an entirely free model (in print and online) but said it would take a brave publisher to do so given the downward pressure on advertising and suggested that it would result in a newsroom comprising "about 15 paid-for journalists".
As for the idea of being paid-for in print and free online, he said: "You can perhaps get away with it for a while...but consumers will work it out in the end."