Twitter's blue ticks were reinstated on some media, celebrity, and other high profile accounts Saturday -- a move protested by many of the recipients.

Once a free sign of authenticity and fame, blue ticks must now be bought by subscribers for $8 a month, Twitter says.

Non-paying accounts that had a blue tick lost it on Thursday, as owner Elon Musk implemented a strategy, dubbed "Twitter Blue", to generate new revenue, announced last year.

Only a tiny fraction of blue-ticked users subscribed -- less than 5 percent of the 407,000 profiles affected, according to Travis Brown, a Berlin-based software developer who tracks social-media platforms.

But on Friday and Saturday, a number of celebrities regained their blue ticks, seemingly without action on their part, including author Stephen King, NBA champion LeBron James and former US president Donald Trump.

Musk tweeted Friday that he was "paying for a few (subscriptions) personally."

American rapper Lil Nas X, whose profile displays the blue tick, tweeted: "on my soul i didn't pay for twitter blue, u will feel my wrath tesla man!"

The accounts of some dead celebrities, such as US chef Anthony Bourdain, also received a blue tick.

Many official media accounts regained a tick, including AFP, which has not subscribed to Twitter Blue.

The New York Times got back its gold badge this month after Musk had bashed the news organization as "propaganda".

The Times is among the major media groups that have a gold tick reserved for an "official business account" paying at least $1,000 a month.

The reinstated ticks did not lure back US public radio NPR and Canada's public broadcaster CBC, which recently suspended activity on their accounts and had not resumed tweeting as of Sunday.

The broadcasters were among those to protest the "state-affiliated" and "government-funded" labels Twitter attached to them, which were previously reserved for non-independent media funded by autocratic governments.

Twitter removed these labels on Friday, including those applied to China's official news agency Xinhua and Russia's RT.