A scheme to licence buskers on the London Underground has been extended after being hailed as a success.
Licensed buskers will now be heard at more Tube stations
A trial period in which only officially approved buskers were allowed to perform in designated areas will continue until the end of the year.
Organisers said there had been an 82% decrease in "busking-related" police call-outs during the trial.
There was less need for police to eject or arrest performers who blocked safety zones or abused staff, they said.
As part of the extension, the number of participating stations will rise from 12 to 17 and new auditions will be held for underground entertainers.
Performers from didgeridoo players to opera singers are among the 300 who already have licences.
About 300 buskers now have official licences
London Underground's busking co-ordinator Richard Smith said: "We launched the scheme because customers said they wanted to hear good music as they travelled around the Tube.
"They've certainly had that and have also played their part in having the trial extended."
Beer brand Carling, which has its logo on the pitches, paid £600,000 towards running costs when the scheme launched and will now pay a further £250,000.
But none of the money goes to the buskers, who still rely on passengers' contributions.