LOS ANGELES-Chart-topping star Justin Bieber reportedly poked fun at US President Donald Trump during the One Love concert in Manchester, England.

Justin Bieber poked fun at US President Donald Trump backstage at the One Love concert in Manchester on Sunday.

The ‘Sorry’ hitmaker reportedly made a joke about the billionaire businessman during Niall Horan’s set at the event in Manchester, which was designed to raise money for the victims of last month’s attack in the city.

A source told The Sun newspaper: ‘’Justin was dancing to Niall’s new song ‘Slow Hands’ and laughed when someone thought it was called ‘Small Hands’.

‘’He quipped, ‘No, that’s our President’. He then added of Niall’s tune, ‘That’s a hit right there’.’’

President Trump has been ridiculed for his supposedly small hands for decades, and it’s something he’s even made reference to during his political campaigning. Justin was joined at the event in Manchester by a star-studded list of performers, including Katy Perry, Miley Cyrus and Ariana Grande. However, Usher - who was originally scheduled to appear at the show - missed the concert to be with his diabetic son on his first day of summer camp. The singer-songwriter took to social media to reveal he wasn’t able to make it to the UK because he was with his son Usher Raymond V. He wrote on Instagram: ‘’So happy to see that last night’s concert in Manchester proved that love always prevails.

‘’I would have loved to be there but It was my son’s first day at Camp Kudzu, one of the few summer camps for kids living with diabetes. This was an important day for him and for myself as a proud father. Stay strong UK. (sic)’’

But, in a previous post, Usher appeared in a video to tell Manchester his heart was with the city.

He said in the clip: ‘’My heart is with you, Manchester. I’m so sorry for all of your loss and all the pain that you’ve gone through. My family and I send our heartfelt condolences to each and every one of you at this difficult time.

‘’We need to love each other. We need to be good to each other. Stay strong, be united, because only through that love can we help we help each other heal.’’