He has also issued assurances to London's Muslim community that the official Eid celebration, held by the Mayor of London every year, will be safe and one of the best yet.
As well as celebrating the end of the Muslim holy month of Ramadan , the event is an opportunity for people from all faiths and backgrounds to remember the victims of the Finsbury Park attack as well as the families affected by the Grenfell Tower fire , many of whom were Muslim.
Mr Khan said he is working closely with Metropolitan Police to ensure the event is safe for everyone to enjoy.
"Eid Mubarak to Muslims here in London and around the world," said the Mayor.
"We’ve been through an extremely difficult time in the capital - since Ramadan began - from the cowardly London Bridge and Finsbury Park attacks, to the terrible fire at Grenfell Tower.
"As a city, we’re still recovering from these events, but I know Londoners will come through both strong and united.
"In these difficult times, it’s been truly inspiring to see how communities have come together in solidarity."
He continued: "Throughout Ramadan, I’ve joined Londoners from all faiths and backgrounds to break my fast at Iftars across our city.
"For me, this is what the holy month is all about – sharing time with others and showing empathy for one another.
"After the long, long fasts of Ramadan, Eid is a time to come together with friends, family and loved ones. Next Sunday, thousands of Londoners will join the capital’s Muslim community at the Eid Festival in Trafalgar Square.
"This huge family celebration will be an opportunity for people from all backgrounds, faiths and communities to celebrate - showing the world that London is open and united. I look forward to seeing you there.
"From my family to yours, Eid Mubarak!"
As well as a global food festival, the Eid Festival will have live music and performances from Muslim artists.
Popular contemporary Muslim artist Siddiqq Juma will offer attendees the chance to make their mark and contribute to an art piece.
There will also be a bazaar style market and an opportunity to visit the I AM exhibition in St Martins in the Fields, celebrating Middle Eastern female artists.
Eid Festival in Trafalgar Square is a free event hosted by the Mayor of London on Sunday (July 2) from noon to 6pm.
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