Elon Musk on Monday announced that Twitter is canceling accounts that haven't been used for a long time.

The move comes as Musk tries to ramp up engagement, and opportunities to make money, at the online platform he bought for $44 billion last year.

"We're purging accounts that have had no activity at all for several years, so you will probably see follower count drop," Musk said in a tweet.

Musk-mandated changes at Twitter from slashing staff to doing away with free verification check marks seen as stamps of authenticity have alienated users and advertisers.

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

Musk tweeted at the time that he was "paying for a few (subscriptions) personally."

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

The reinstated ticks did not lure back US public radio NPR, which in mid-April suspended activity on its accounts.

The broadcaster was 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.

Since Musk bought Twitter, the company has relaxed the moderation of content on the network, letting back many users banned because of messages inciting hatred or spreading misinformation.

Market trackers say Twitter revenues have fallen as advertisers avoid the platform.