Sir Sadiq Khan has said that he and the King discussed which of them is "a bigger workaholic" as he received a knighthood for political and public service.
The politician, who is the first London mayor to win a third term, was knighted by Charles in a ceremony at Buckingham Palace.
Speaking to the PA news agency, the 54-year-old said: "I have got the pleasure of working closely with the King.
“We were just comparing who’s a bigger workaholic. He was very chuffed that he managed to personally give me this honour and he actually apologised for it taking so long – which is not a problem at all."
Sir Sadiq, a second-generation immigrant, said he was delighted to receive a knighthood with his family in attendance.
He remarked: “My mum’s here, and she’s been emotional since it was announced on January 1, and today’s just a great day for the family.
“Obviously, from my background, being the son of immigrants, my parents coming here from Pakistan, it’s a big deal for us.”
Asked what he is proudest of in his time as the Mayor of London, Sir Sadiq said free school meals for primary school children, “cleaning the air and investing in affordable housing”.
“What I’m really proud of is the chance to work with Londoners, like His Majesty.”
Sir Loyd Grossman, who was knighted at the same ceremony, said London is “the greatest city in the world”.
The 74-year-old broadcaster and author, known widely for his range of cooking sauces, was awarded a knighthood for services to heritage, having led the transition of The Royal Parks, as chairman, from a government agency through to its establishment as an independent charity.
Born in Massachusetts in the US, Sir Loyd came to England in his mid-20s.
“I’ve always felt that our heritage is so important to us, because not only is it beautiful, it’s also inspiring,” Sir Loyd said.
“It helps us realise what it’s like to be citizens together.
“It’s one of the things that we do better in this country than anywhere in the world.
“People all over the world, when you ask them about London: what is it that’s so great about London – which is the greatest city in the world – almost always they say your parks.”
He said The Royal Parks were a lifeline for Londoners in lockdown, but that he “couldn’t possibly say” which is his favourite.
“The first one I ever went to, when I came here as a student, was Kensington Gardens, so I have a particularly strong affinity for Kensington Gardens but I just love all of them.”
Dame Emily Thornberry, who has been Labour MP for Islington South and Finsbury since 2005, was formally made a dame at Buckingham Palace.
The chairwoman of the Foreign Affairs Select Committee, 64, said she does not usually get nervous but was “fizzy with nerves” after receiving the honour.
Dame Emily, who was honoured for political and public service, wore brooches belonging to her mother and grandmother in her hat at the ceremony.
“My grandmother used to work for Lloyds Bank and she wasn’t allowed to work after she got married. If she knew that I’d become a dame, she wouldn’t believe it,” the former shadow foreign secretary said.
“Neither would my mum.”
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