Prince William makes first public appearance since Prince Harry's historic two days in court

Prince William has been seen publicly for the first time since his younger brother appeared in a London courtroom.

Prince Harry's historic two-day appearance in the witness box in the High Court earlier this week was the first by a British royal in more than a century.

While the Duke of Sussex gave evidence in his case against a UK tabloid, the rest of the British royal family largely stayed out of the public eye, with only the Princess of Wales making appearances in Windsor while her brother-in-law was in London.

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On Thursday, a day after the duke wrapped up in court, his brother the Prince of Wales appeared at the Royal Marsden Hospital in Sutton, London, to open a new cancer centre.

William is president of The Royal Marsden, following in his mother Princess Diana's footsteps, and has regularly made visits with patients there.

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The Prince of Wales channelled his late mum when he lay the foundation stone in 2020.

The pictures were reminiscent of 30 years earlier, when Diana laid the foundation stone for a wing of the Trust's West London hospital in June 1990.

On his arrival the Prince of Wales met a nurse he worked with during his work experience as a student at St Andrew's 18 years earlier.

"We've met before," he told her before explaining where they'd crossed paths.

William began the day by quite literally rolling up his sleeves, sanitising his hands and meeting some of the patients inside the new centre.

The 40-year-old was seen laughing with people of all ages as they sat in treatment chairs and looked on intently as he spoke with researchers.

William also met with a number of outpatients, including one whose first reaction to meeting the royal was "you're a tall bugger, ain't ya?" to which William laughed heartily.

"And your wife's not bad, she's a nice lady as well," the man later told William, to which he agreed.

"He's a chatty one, I think," William said to the man's wife with a laugh.

The prince then delivered a speech and unveiled a plaque declaring the centre officially open.

"I was so pleased to hear first-hand from patients this morning what a difference this building will make to them," he said.

William said the opening of the state-of-the-art facility "will transform the lives of cancer patients".

He was "incredibly proud" to be in the Oak Cancer Centre eight years after first launching the appeal for the project.

The Prince of Wales, who has been in his role with The Royal Marsden NHS Foundation Trust since 2007, dressed in a navy suit with a matching tie for the occasion.

His outing came days after William and wife Kate returned from a quick trip to Jordan for the royal wedding of Queen Rania's son Crown Prince Hussein to Rajwa Al-Saif.

His father, King Charles III, is on a private trip to Romania this week, so it's expected neither Prince William nor His Majesty will be meeting with Prince Harry during his short visit to the UK.

The brothers have a strained relationship, which Harry detailed in his explosive memoir, Spare, released in January.

It revealed the depths of their rift with allegations of an assault and shouting matches. Prince William has never publicly commented on his brother's claims.