Doves have been released at Notting Hill Carnival as a tribute to those who died in the Grenfell fire tragedy.
The official opening ceremony saw the charity single Bridge Over Troubled Water performed and a multi-faith prayer was said.
London Mayor Sadiq Khan said although the 51st carnival took place in a "context of sadness and sorrow", it was a celebration of London's diversity.
At 15:00 BST, sound systems were turned off to mark a minute's silence.
Firefighters and paramedics were among those who bowed their heads in tribute to victims. Another silence will be observed on Monday.
The carnival route passes near the tower and a "ring of care" has been formed around it by police.
More than 80 people are believed to have died in the fire on 14 June.
The white birds were released from the hands of survivors and local residents, as well as leader of Kensington and Chelsea council Elizabeth Campbell, Mr Khan and local MP Emma Dent Coad.
Hamid Ali Jafari, 33, whose 82-year-old father Ali Yawar Jafari was killed in the blaze, helped to release the doves.
Asked how it felt, he said: "It's the pain of remembering my dad, because he was there."
Earlier, the carnival got under way with a traditional paint fight.
The tradition, known as Jouvert, meaning "open of the day", sees revellers hurl paint at each other which dancing to steel bands and African drummers.
Handmade green hearts and streamers adorned the judging area, while spectators were decked out in green following a campaign encouraging people to go "green for Grenfell", which organisers said they hoped would symbolise "reverence and respect amidst the revelry".
In her speech, Ms Dent Coad, who had previously likened the carnival to a wake, praised the "Grenfell generation" of young people and urged them to set aside sadness and worries.
"Carnival is for dancing, laughing, singing along and having a wonderful time with our community and those closest to us," she said.
At the scene: BBC reporter Mark Lobel
Thousands of energetic performers with strikingly colourful costumes are entertaining tens of thousands lining the streets in west London in stunning weather.
There is, above all, a relaxed and joyous atmosphere despite the sombre tone interspersed into proceedings.
Doves were released for the victims of the Grenfell Tower fire after a street service attended by religious and political leaders at which the mayor was applauded for saying those responsible for the fire that killed at least 80 people half a mile from here need to be held to account.
Some people are wearing green in honour of the victims and messages of remembrance and anger have been drawn onto wooden hoardings and metal stalls.
Summing up the poignancy of this year's annual party, Hackney-based dancers Muraldo Mass in flowing blue iridescent hooped dresses and camouflage tops, told me they wanted to dance here to show Grenfell survivors they are supported by a community not just based locally, but from across the city.
Pepe Francis, chairman of the carnival trust, said: "This will be the first opportunity for visitors to Carnival to pay their respects for those affected by Grenfell."
Hundreds of hand-drawn tributes, flowers and candles will be protected by fencing, while the public have been asked not to take selfies at the site.
A reflection zone will be placed near the burnt high-rise, where performers will lower the volume of their music.
A spokesman for Grenfell United, a residents and survivors group, said: "We hope people will follow these requests from us and our friends and family in the wider community.
"They will enable people to pay their respects; be conscious of our vulnerability; and show solidarity for our ongoing demands for housing and full justice, in the creative spirit of Carnival."
Steel barriers, concrete blocks and a ban on vehicles will be in place to protect revellers from the threat of terrorism.
Scotland Yard said there was no specific intelligence but security plans had been "thoroughly reviewed" after the Barcelona attack.
Are you going to Notting Hill Carnival? We would like to see your photos and hear about your experiences. E-mail us at firstname.lastname@example.org
Please include a contact number if you are willing to speak to a BBC journalist. You can also contact us in the following ways: