Ariana Grande's manager released a statement about the situation earlier today
In a statement released on Sunday, Grande and Justin Bieber's manager Scooter Braun said the tribute concert will be to "honour those lost" in both the Manchester and London's atrocities.
"After the events last night in London, and those in Manchester just two weeks ago, we feel a sense of responsibility to honour those lost, injured, and affected," he said.
"We plan to honour them with courage, bravery, and defiance in the face of fear."
"Today's One Love Manchester benefit concert will not only continue, but will do so with greater purpose."
Tonight's show will raise money for the We Love Manchester Emergency Fund, and will feature A-list acts such as Coldplay, Katy Perry, Usher, Take That and Miley Cyrus.
Ariana Grande took to Twitter earlier today to express her sadness over the London attack, saying: "Praying for London".
Greater Manchester Police assistant chief constable Garry Shewan also issued a statement following Saturday's attack, which left seven dead and 48 injured.
"We're deeply saddened to hear about last night's horrific attacks in London and our thoughts are with everyone affected," he said.
Praying for London ♡— Ariana Grande (@ArianaGrande) June 4, 2017
Police have urged those attending the benefit concert "not to bring bags if they can", in order to speed up entry.
The attack came less than two weeks after the bombing at the end of an Ariana Grande concert at the Manchester Arena on 22 May, which left 22 people killed and 116 injured.