Officials say security will be bolstered for "One Love Manchester", which aims to raise money for those affected by the bombing that killed 22 people and wounded more than 100 at Grande's May 22 concert.
"There will be additional security checks taking place and everyone will be searched, including bags".
All artists involved have been unwavering in their support this morning and are determined to carry on with the show.
The announcement comes in the wake of an attack that killed seven people.
Peter Mann, whose daughter Jaden was injured in the attack, wrote of Grande's hospital visit: "This means more to us than all the incredible things people have done this week".
Grande surprised young fans injured in last month's attack with a visit to the Royal Manchester Children's Hospital on Friday.
"I just think we need to try and be as normal as possible and just not have that panic about us, not have panic or anything", She tweeted after the London attacks on Saturday.More news: London Bridge terror attack: Ariana Grande 'praying' for victims before Manchester concert
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More than 10,000 people applied for free tickets to the concert despite not attending the original gig.
Ariana Grande's concert benefiting the victims of the Manchester attack will now also honor the victims of Saturday, June 3rd's London attacks, People reports. Meanwhile, police investigating the Manchester Arena attack, which killed 22 people, have made a further arrest.
But Will.i.Am was barraged with messages on Twitter after he mistakenly referred to Manchester as London twice on his set at the One Love benefit concert.
The Old Trafford cricket ground has a 50,000 capacity and tickets sold out within 20 minutes when they went on general sale.
Adam Harrison told the BBC his daughter Lily "felt like a rock star" after meeting her idol late on Friday and was "chomping at the bit" to attend the concert. Disney's young adult cable network Freeform will air the full concert live at 2 p.m. EDT on Sunday.
In the United Kingdom, the three-hour show is going to be broadcast on BBC One and streamed live on the BBC iPlayer.
Three men, wearing hoax explosive vests, then left the van and began to stab revellers and a British Transport police officer with 12-inch knives before being shot dead by police at Borough Market.