Britain's top-selling newspaper The Sun, which is owned by Rupert Murdoch, on Thursday began charging readers for access to its website.
Known for its celebrity scoops and topless "page three" models, the tabloid will charge subscribers £2 ($3, 2.30 euros) for a week's access to its website, which will be called Sun+.
Murdoch's British newspaper publisher announced the paywall in March, saying free access to The Sun's online content had become "untenable".
"Asking readers to pay for content is the only way to protect the future of the newspaper industry," said the Sun's new editor David Dinsmore.
"This is a landmark event for The Sun and a testament to the pioneering attitude of Britain's best-selling newspaper."
A slew of the world's top newspapers have started charging for online content in recent years, including The New York Times and the Murdoch-owned Wall Street Journal.
The Australian-born media tycoon, 82, placed his British broadsheet The Times behind a paywall in 2010.
The Sun sold around 2.24 million copies a day in June, a Sun spokeswoman told AFP -- compared to 3.12 million copies four years ago.
"Like the other newspapers, there has been a decline in readership in the past years," the spokeswoman said.
The Sun's website, Sun+, currently attracts around 32 million unique users per month, she added.
Sun+ will attempt to attract subscribers with "near-live" video clips of English Premier League football goals as well as discounts and promotions.
While The Times' print subscribers get automatic access to its website, The Sun's print subscribers will need to collect 20 codes from their papers in order to access online content for the next month, in a process the spokeswoman admitted was "quite tricky".
Putting The Sun's website behind a paywall is a big gamble for Murdoch, who saw traffic to The Times' site drop off heavily after it began charging for access to online content.
Mike Darcey, CEO of Murdoch's renamed British newspaper wing News UK, insisted last month that the paywall was "working" and that The Times' income from subscriptions was higher than it was in 2010.
"Initially thought of as a crazy move, it has been successful and is now flattered by widespread imitation," he told a conference.
A spokeswoman for The Times and its sister newspaper, The Sunday Times, said the two websites currently have some 274,000 subscribers.
The Times' parent company Times Newspapers Limited reported pre-tax losses of £28.7 million ($43.6 million, 32.9 million euros) in the year to June 2012.