But the prime minister’s spokesperson repeatedly refused to say whether he shared the Queen’s view, instead referring back to his previous comments on the right to protest.
“He has always supported the right of people to protest and make their feelings known about injustices,” he told The Independent.
The comments come after the prime minister was criticised for initially refusing to criticise fans who booed England’s football players for taking the knee before matches.
Mr Johnson and Priti Patel were accused of having given “license to the racists” who abused the black players who missed crucial penalties in the Euro 2020 final.
The home secretary went further last year, saying she opposed the BLM demonstrations that swept the country in the wake of the US murder, saying: “Those protests were dreadful.”
On Thursday, Sir Ken Olisa, the lord lieutenant of London, said: “I have discussed with the royal household this whole issue of race, particularly in the last 12 months since the George Floyd incident.
“It’s a hot conversation topic. The question is what more can we do to bind society to remove these barriers. [The royals] care passionately about making this one nation bound by the same values.”
Asked, in an interview on Channel 4, whether that meant the palace supported Black Lives Matter, Sir Ken replied: “The answer is easily yes.”
Mr Johnson’s spokesperson, asked the same question, replied: “He’s been asked this question himself before, and he’s spoken about the fact that he’s proud that the United Kingdom is a tolerant and diverse country.”
Pressed on whether that amounted to support, the spokesman added: “I’m saying what he said himself – he supports the right of people to make their feelings known about injustices.”
Mr Floyd who was killed by police in Minnesota in May 2020, sparking a historical wave of anti-racism protests across the globe under the banner of Black Lives Matter.
The aide’s comments come after the Duke and Duchess of Sussex accused the royal family of racism in their Oprah Winfrey interview earlier this year.
Meghan said an unnamed royal – not the Queen or the Duke of Edinburgh – raised concerns with Harry about how dark their son Archie’s skin tone might be before he was born.
The couple also suggested racism could be a factor behind the decision to deny Archie, the first mixed-race great-grandchild of the Queen, security protection or the title of prince.
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