Prince Harry joined a dazzling line-up of celebrities at the Attitude Awards in London on Thursday night.
The 33-year-old royal looked dashing in black tie as he joined stars including Kylie Minogue, Amanda Holden and Myleene Klass for the glittering ceremony at the Roundhouse in Camden, north London.
The prince was on hand to collect a posthumous Attitude Legacy Award on behalf of his mother, Princess Diana, and in doing so became the first member of the royal family to pick up an honour at a gay awards ceremony.
Diana was recognised for her significant work in drawing attention to HIV/AIDS.
Stepping on to the stage, Harry charmed the audience when he quipped flirtatiously: 'Don't we all look lovely? Can I stay?,' before praising his mother's tireless efforts.
In a heartfelt speech, he said: 'William and I are incredibly proud of what our mother achieved.'
He said that his mother 'felt a responsibility to shine her spotlight on the people and issues that were often ignored'.
He said his mother was only 25 and still finding her way in public life when she chose to shine a spotlight on Aids.
'She knew that the misunderstanding of this relatively new disease was creating a dangerous situation when mixed with homophobia. People were being ostracised from their communities - and sometimes from their families - simply for being ill.'
'When she shook the hand of a 32-year-old man with HIV in front of the cameras, she knew exactly what she was doing,' he said.
'She was using her position as Princess of Wales - the most famous woman in the world - to challenge everyone to educate themselves; to find their compassion; and to reach out to those who need help instead of pushing them away.'
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Dazzling: Prince Harry poses with his arms around Kylie Minogue as the pair attend the Attitude Awards in London
Proud: Prince Harry, left, receives a posthumous Attitude Legacy Award on behalf of his mother Diana, Princess of Wales, from Ian Walker, right, and Julian La Bastide at the Attitude Awards in London on Thursday night
Hitting the right notes: Amanda Holden, left, and Louisa Johnson, right, led the glamour at the star-studded Attitude Awards
Pop princesses: Pixie Lott, left, and Little Mix's Jade Thirlwall, right, were among the celebrities who attended the ceremony
The ceremony, which was hosted by Tom Daley, recognises the 'inspiring stories and outstanding achievements' of key figures in the LGBT community.
Guests included Kylie Minogue, who received a 'legend' award, Matt Lucas, Sam Smith, Chris Robshaw, Beverly Knight and Little Mix's Jade Thirlwall.
Among the stand-out red carpet looks was X Factor singer Louisa Johnson, who turned heads in a plunging tangerine gown with a daring thigh-high slit.
As he walked on the stage Harry, whose appearance at the ceremony was a surprise to most of the audience, immediately won them over with his flirty quip.
Pioneer: Prince Harry tonight became the first member of the royal family to pick up an honour at a gay awards ceremony
Charming: Harry wowed the crowd as he delivered a speech praising his mother's pioneering work highlighting HIV/Aids
Prince Harry's tribute to Princess Diana in full
Legacy: Harry paid tribute to his mother's work in a speech
'In April 1987, my mother was only 25 years old.
'She was still finding her way in public life, but already she felt a responsibility, to shine her spotlight on the people and issues that were often ignored. She knew that AIDS was one of the things that many wanted to ignore and seemed like a hopeless challenge. She knew that the misunderstanding of this relatively new disease was creating a dangerous situation when mixed with homophobia.
'People were ostracized from their communities – and sometimes from their families – simply for being ill. Staff who treated the ill, were themselves often turned away from local barbers and restaurants, even though it was proven that HIV could not be passed on from casual contact.
'And we faced the very real risk that thousands would die in the UK – including many young gay men of her generation – without making any progress towards treatment of the disease.
'So when that April, she shook the hand of a 32-year-old man with HIV, in front of the cameras, she knew exactly what she was doing. She was using her position as Princess of Wales – the most famous woman in the world – to challenge everyone to educate themselves; to find their compassion; and to reach out to those who need help instead of pushing them away.
'In the years that followed that famous handshake, her work continued, both in public and private. When she visited Mildmay Hospital and the London Lighthouse hospice, she wanted the world to learn the stories of those who were dying. She wanted people to demand action towards treatments that would save lives. And she wanted to get to know those who were dying not as statistics or patients, but as people.
'In the year before my mother's death, the first truly effective anti-retroviral treatments were developed for HIV and AIDS. She did not live to see this treatment become widely available and save countless lives in the UK and around the world.
'I often wonder about what she would be doing to continue the fight against HIV and AIDS if she were still with us today.
'I believe that she would be telling everyone across society – not just those most at risk – that with effective treatment being free and available in the UK, that we must all embrace regular testing – both for our own sake and for those that we love.
'She would be demanding that same access to treatment and testing for young people in Africa and across the world. And she would of course be standing alongside those who are living openly, as healthy, happy and HIV-positive.
'William and I are incredibly proud of what our mother achieved. And we thank you for awarding her the Legacy Award.'
Standing out: The former X Factor winner was more than confident to show off her killer figure in her orange gown, which featured a daringly plunging neckline
Think pink: Joining her on the carpet soon after was Pixie Lott, who looked equally as glamorous in a pastel pink gown, adorned with sequin flowers all over
Princess Diana is revealed as Attitude cover star
Honoured: Princess Diana features on one of six limited edition covers of Attitude magazine's awards issue, available now
Princess Diana will feature on the front cover of Attitude magazine after winning the publication's legacy award.
The stunning limited edition cover - a black and white photograph of the former royal by Patrick Demarchelier - was unveiled during the magazine's annual awards ceremony on Thursday night.
The posthumous award recognises the significance of Diana's work in challenging the stigma and fear that surrounded HIV and Aids in the 1980s and 1990s.
The magazine cover adds to a long list that Diana amassed before her death at the age of 36, including the likes of Vogue and Vanity Fair.
Darren Styles, managing director of Stream Publishing and publisher of Attitude magazine, said: 'Behind Diana's famous beauty and style, there was a radical firebrand driven by a passion for activism.
'Very few individuals had the power to change the mindset of millions of people at that time, but Diana knew that she was one of them - and she chose to wield her power to improve the lives of gay men suffering with HIV/Aids.'
'Without the expected mask, gown or gloves, she touched and embraced the sick and the dying, when the common misconception was (that) sharing cutlery or a public bathroom would see you infected.
'It changed understanding and it changed our world. 2017 may mark 20 years since the death of the princess, but it also marks 30 years since the start of her HIV activism, and her opening of the UK's first hospital unit dedicated to HIV/Aids.'
Attitude's Diana artwork forms one of six limited edition winners' covers following Thursday's awards, which support the Elton John Aids Foundation.
He went on: 'I often wonder about what she would be doing to continue the fight against HIV and Aids if she were still with us today.
'I believe she would be telling everyone across society - not just those most at risk - that with effective treatment being free and available in the UK, that we must all embrace regular testing - both for our own sake and for those that we love.' A video of the speech was shared on the Attitude Magazine Twitter account.
The appearance reflects Harry's desire to carry on his mother's work, and his commitment to campaigning on HIV/Aids. He has publicly taken an HIV test to emphasise the importance of testing, and set up a charity - Sentebale - to help children in Lesotho affected by the condition.
The award, which was marked by Diana featuring as one of six limited edition winners' covers, was introduced by two former health workers who both met Diana. Ian Walker was a senior occupational therapist at the London Lighthouse, the former Aids centre in west London which Diana often used to visit, and Julian La Bastide was a nurse at the Mildmay Hospital.
Commanding attention: Pulling into a sweetheart neckline to display the former Girls Aloud star's delicate decolletage, the dress then cinched in at her slim waist before cutting off high at her thigh, to leave her shapely pins on display
All that glitters: Mel was also joined by actress Laverne Cox, who opted for a more glamorous black dress, embellished with chunky gems on one side
Let's hear it for the boys: Representing the men at the bash were Tom Daley (L), who was hosting proceedings, and Sam Smith (R) - who both cut impeccably suave figures in their respective suits
Mr Walker, who met Diana several times between 1993 and 1997, said: 'She filled the room and she gave off light. Everyone was immediately put at ease, and just the fact that she would come in, talk to someone, hold their hand, that would mean that maybe the next day they died happy because Diana had spoken to them.'
Recalling the pivotal moment when she shook hands with an Aids patient, he added: 'It seemed to break down a million barriers overnight with that one simple act. This was a time when people were terrified to touch people with HIV, people would glove, mask and gown up in regular hospitals. People were rejected by their families, people would feel really uncomfortable when they saw you walking around. She held that guy's hand and overnight this dispelled a lot of the stigma.'
Mr La Bastide, a nurse at the Mildmay Mission for 17 years, recalled the effect of Diana's work. He said: 'My patients and people I worked with felt that they were important, that someone was taking their cause — their fight — to another level. Diana wasn't making that distinction of 'these people are more important or less important'. It was, 'you are all important'. And she knew that every time she did an announced visit with the cameras there, that would go mainstream.'
A Kensington Palace spokesman said: 'Prince Harry was keen to do this as he has continued his mother's work on HIV/Aids and the awards are in support of the Elton John AIDS Foundation who he has worked closely with.'