Justin Bieber’s grandmother reckons the teen sensation should perform a free London concert to make amends to fans after his trouble filled trip to the UK.

The 19-year-old singer’s recent trip to the UK hit the headlines for several reasons this week, and not all of them were good.

The Baby hitmaker showed up two hours late for a show at London’s O2 Arena and he was also caught on camera trying to attack a photographer.

Speaking to the Daily Star Sunday newspaper Bieber’s grandmother, Kathy, admitted that her grandson has fallen in with the wrong crowd and needs to make it to his fans for his antics this past week.

Kathy said: ''I don't think for one moment this is all about him being a bad boy. He's only just turned 19 and he's still learning to cope with the pressures of fame.

''But it's worrying. You read all sorts of things about him partying and he needs to understand some of those so-called friends probably don't have his best interests at heart.

'I know he will be feeling depressed about the way things have gone in London, so maybe it would be a good idea if he were to go back there later and perform free for the fans who feel let down by him.''

Meanwhile, the Sunday People has reported Bieber is acting out of character because of his split from Selena Gomez in January after around two years together.

A source told the newspaper: ''He simply hasn't been the same since he split from Selena. It really broke him.

''They were together for such a long time for two people so young. He hasn't quite known what to do without her.

''He is lonely. They kept each other very grounded and understood the level of fame that they both had. Now his friends know he needs their support more than ever.''