Prince Harry made a surprise appearance at a black-tie gala for Ukraine in London on Thursday night, while his estranged brother Prince William made a virtual appearance at another charity ball just a few miles away.

The Duke of Sussex smiled and waved in a tuxedo, followed by his bodyguard, as he arrived at the United for Freedom gala at the Imperial War Museum in central London.

Meanwhile, in west London, the Prince of Wales was supporting the inaugural Bowelbabe Fund Rebel Ball, held on what would have been Dame Deborah James's 45th birthday.

William had spent the day in Wales but sent a video message to be played at the event, praising Dame Deborah's 'rebellious hope' and the extraordinary fundraising legacy that continues after her death.

The diary clash came as Harry carried out yet another public engagement in Britain following his family's return to the UK in late August.

Earlier on Thursday, Meghan launched a £112 ($148) advent calendar in her first commercial venture since relocating. The calendar, featuring 24 gourmet chocolates said to be inspired by her Montecito home and garden, also includes a festive illustration of the £11million mansion she and Harry called home for six years.

Harry, meanwhile, continues to focus on his charitable causes. The United for Freedom gala was held to raise money for organisations supporting Ukraine as the war entered its fourth year earlier this year.

He spoke at the event about the historical ties between Britain and Ukraine before sharing his own experience during recent trips to the war-torn nation.

'I have seen something in Ukraine that makes it impossible for me to look away. I have met people who have lost limbs, lost homes and lost loved ones -  and yet somehow find the strength to rebuild,' said the Prince. 

Harry also praised the resilience of the Ukrainian people who defend the frontline while also keeping businesses and schools going all while 'developing technology that is changing the nature of modern warfare'.

He continued:  'But their resilience should never become an excuse for the rest of us to tolerate their suffering. Ukrainians should not have to prove, year after year, just how much they can endure.' 

'Their courage deserves more than our admiration. It deserves our resolve.'

Meanwhile, his brother the Prince of Wales was involved in an event just six miles away at Fulham's Hurlingham Club. 

Guests made a surprise appearance via a pre-recorded video message at the inaugural Bowelbabe Fund Rebel Ball.

The gala took place on what would have been campaigner Dame Deborah James's 45th birthday, who died from bowel cancer in June 2022, to raise money for the late journalist's charity and Cancer Research UK.   

Paying tribute to Dame Deborah, William said: 'What struck me was Deborah's positivity and humour in the face of adversity – what she liked to call 'rebellious hope'.'

He went on to describe Dame Deborah as 'an amazing woman' and said her Bowelbabe Fund for Cancer Research UK had achieved so much in the last four-and-a-half years, investing in pioneering research that was 'giving more people more time with the ones they love'.

Heir to the throne William told guests including Dame Deborah's friends and family: '

'Tonight is about honouring the legacy of Dame Deborah James, an amazing woman who achieved and continued to achieve so much in pursuit of saving and improving lives.'

'I had the privilege of meeting Deborah back in 2022, and presenting her with her damehood in her parents' garden.

'We talked then about her incredible achievements, her ambitions and her desire to leave a lasting legacy through the Bowelbabe Fund for Cancer Research UK.'

'What struck me was Deborah's positivity and humour in the face of adversity - what she liked to call 'rebellious hope'.

'Fuelled by that positive spirit the Bowelbabe Fund for Cancer Research UK has achieved so much over the last four and a half years, as it continued to invest in pioneering research that's giving more people more time with the ones they love.'

'Tonight would have been Deborah's 45th birthday and I know she would have wanted everyone dancing, celebrating and making memories.'

'I hope you all have a wonderful evening celebrating the legacy of the incomparable Dame Deborah James.'

The fundraising ball, which was hosted by TV presenter Gaby Roslin in London, featured performances by Sophie Ellis Bextor and the West End cast of the production Disco Inferno.

Dame Deborah's husband Sebastien Bowen said: 'On what would've been Deborah's 45th birthday, we wanted to honour her memory and the Rebel Ball captured so much of what made her special: her energy, her courage and her ability to bring people together behind a cause she believed in.'

The Bowelbabe Fund for Cancer Research UK supports cutting-edge research and raises awareness of bowel cancer.

It was launched by Dame Deborah in May 2022 with an initial target of £250,000.

The You, Me And The Big C podcast host, who was diagnosed with bowel cancer in 2016, was given a damehood for her fundraising efforts, which soared into the millions.

Harry and Meghan, who returned to live in the UK just over a month ago, are waiting to hear whether they will be given taxpayer-funded security.

They pulled Archie and Lili out of their first-choice British school in September after just two days when heavy traffic in the area meant their private security team struggled to stay in a convoy during the school run.

The Sussexes stepped down as working royals in 2020 for personal and financial reasons but rumours remain rife as to why they unexpectedly relocated to the UK from California.

Speculation ranges from the couple wanting their children to develop a closer relationship with their grandfather King Charles, Meghan seeking a return to acting and the Sussexes wanting to increase their profile.

In the run-up to their return, Charles was said to be glad to be able to spend more time with the family but remained adamant they would not be working royals, and there was no half-in, half-out option.

Within two weeks of arriving, there was reported pushback from Harry and Meghan after a letter, authorised by the King, was circulated by the Lord Chamberlain to senior stakeholders in the Government and military reiterating the couple were 'private citizens' and setting out guidance on how they should be treated.

The duke and duchess were said to be 'surprised' by the formal letter and the couple, who are waiting to hear whether they will be given taxpayer-funded security, were reported to prefer the term 'public figures' instead.