Survivors of the Grenfell Tower fire have gathered ahead of a memorial at St Paul's Cathedral, which will be attended by members of the Royal Family and the prime minister.
Grenfell fire: Families and survivors gather for St Paul's memorial
About 1,500 people are invited to the multi-faith service, including the bereaved, survivors and rescue workers - writes bbc.com
Joining them are the Prince of Wales, Duchess of Cornwall, Duke and Duchess of Cambridge and Prince Harry.
The service, at 11:00 GMT, will remember 71 people who died.
The service will also give thanks to everyone who assisted on the ground at the time of the tragedy and since it - including the emergency services, the recovery team, the community, public support workers and volunteers.
Bishop Graham Tomlin, Bishop of Kensington and organiser of the service, said there were still "so many unresolved issues in the community".
"It's very difficult to live with that level of uncertainty," he told the Victoria Derbyshire programme, adding: "At the same time I think we do want to say that it is possible for life to be rebuilt."
"There was a very strong desire within the local community to have the service here, because faith is very important to a lot of people in the local area, and that can bring a real sense of strength to people."
One of those in attendance will be Tiago Alves, who escaped the blaze with his family.
He told BBC Breakfast his thoughts would be with bereaved families during the memorial: "Today is a day not about survivors; today is purely about the bereaved, their families and the loved ones they have lost."
He said the memorial was going to be "quite emotional" and would bring back a lot of awful memories for many people.
But he added: "The reason we are doing this today is so that people never forget - we want people to remember."
Clarrie Mendy, who lost her cousin Mary and Mary's daughter, Kadije Saye, in the fire, said the service was "what the community needs, what the survivors need".
"It is a very emotional day," she said. "I just hope everybody will get something from it."
Councillor Elizabeth Campbell, leader of Royal Borough of Kensington and Chelsea, will not attend the service, after some families said they did not want the council there in an official capacity.
The final death toll from the fire was put at 53 adults and 18 children, including stillborn baby Logan Gomes, following an arduous process of recovering and identifying remains from the block.
During the service a banner with the Grenfell Heart will be displayed, while there will be performances from the Ebony Steel Band, Portobello Road Salvation Army Band, an Islamic girls' choir from the Al Sadiq and Al Zahra Schools, and St Paul's Cathedral Choir.
A pre-recorded sound montage of anonymous voices from the Grenfell community will also be played.
At the end of the service, which will also be attended by Theresa May and Labour leader Jeremy Corbyn, bereaved families and survivors will leave the cathedral in silence, holding white roses.
Meanwhile, Met Commissioner Cressida Dick said the force would do "whatever it takes" to bring to justice anyone who had committed a criminal offence linked to the fire.
Ms Dick said officers would investigate "meticulously, fairly and fearlessly", but said she would be "vey surprised" if the criminal investigation was completed within the next 12 months.
Scotland Yard has previously said it will be considering both individual and corporate manslaughter charges.
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