作為組織者所稱的 "歷史上最大和最具包容性的活動 "的一部分，將有一個藝術家陣容在倫敦市中心的四個舞台上表演。
As part of what organisers are calling the "biggest and most inclusive event in history", there will be a line-up of artists performing across four stages around central London.
Mohammed Nazir, 24, from Bangladesh, from campaign group Rainbows Across Borders, said he wanted to dedicate this year's pride to those who were still forced to hide their sexuality.
"We saw this time last week an attack in Oslo just hours before that parade, where two people lost their lives and more than 20 were injured," the Labour mayor said.
"So, we've got to be conscious of the fact that there's still a danger to this community of discrimination, bias and violence. But allies like me are really important to support this community.
"We're also marching today for love. In this great city we should be a beacon of inclusiveness, of openness, but also a place where you can be free to be who you want to be and free to love who you want to love."
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