The What Do You Mean? singer was irked by fans' timekeeping during a performance of his latest hit, and decided to show devotees how to clap along.

In video from the gig, which has gone viral, Justin can be heard saying, "At least clap on the right notes. Come on guys. Stop, stop, stop."

He then gave them an example, stating, "It's like this. If you're going to clap, at least clap on beat."

The latest odd moment from Bieber's European promotional tour comes days after he walked out of a radio interview in Spain and then stormed offstage during a gig in Oslo, Norway after fans mocked him and tried to grab him as he attempted to mop up spilled water at the front of the stage.

Meanwhile, the pop star has given Icelandic officials cause for concern after taking a dip in a freezing glacial lake - because they're worried his fans might follow his lead, risking hypothermia or even death.

Bieber took the plunge in the Jokulsarlon lagoon for his new I'll Show You music video, and now local tourism bosses are keen to stop his Beliebers from copying him.

A spokesman for local tour company Jokulsarlon feroapjonusta ehf tells the water temperature ranges between three and minus-three degrees Celsius, which is perfect for icebergs, but not for people.

The local expert also reveals the lake is so remote that the nearest town is over an hour away.

He says, "There are no actual rules against swimming - it's just stupid."