Sofia Richie is ''annoyed'' at how Justin Bieber handled their relationship.

The 22-year-old pop megastar split from the Sofia, 18, after just a month of dating in September, and sources have claimed that despite calling time on their romance, the pair ''still communicate''.

A source told E! News: ''Sofia is still kind of annoyed at how Justin handled a few things, but they still communicate. They haven't hooked up in a minute.''

The news comes after Sofia - who is the daughter of musician Lionel Richie - was spotted at the 'Sorry' hitmaker's concert in London earlier this week.

Another source said of their relationship previously: ''They are still friends though and will continue to see each other like they did before they were dating. They are taking a backseat though on the romance side of things and just focusing on being friends at this time.''

However, despite the model's attendance at the show, there's nothing romantic between the pair.

The insider said: ''Sofia and Justin are not back together, and they never were an official couple. They just hooked up and were close friends.

''Sofia is chill with the whole situation and not ruling out future possibilities with Justin, but as of this second nothing is happening.''

The 'Love Yourself' musician ended the pair's fling last month, after concerns that things were getting too ''hot and heavy'' when he wasn't interested in anything serious.

A source said at the time: ''It was super-hot and heavy, and because Justin doesn't want a relationship right now, he wanted to cool things down. It wasn't an intentional cool-off. It just sort of happened on its own.''