Prince William rubs shoulders with singer Joss Stone at conservation ball

While his wife the Duchess of Cambridge, née Kate Middleton, attended her first official public engagement on Thursday, Prince William had an engagement of his own come evening, as he took to the stage as the guest of honour for the inaugural Tusk Trust conservation ball.

The Duke of Cambridge was in good company at the black-tie event for a charity which works to protect Africa's wildlife, chatting to singer Joss Stone, who is known for her charity work and also supports animal welfare charity PETA.

Prince William greets singer Joss Stone, who entertained guests at the ball

The pair were clearly delighted to meet, pictured smiling gleefully as they greeted one another. The Duke was smart in a black tuxedo and bow tie while the songstress – who later performed for guests – donned a lace white dress with a no doubt faux fur coat.

Others among the 500-strong guest list included Dragons' Den stars Deborah Meaden, a Tusk Trust patron, and her guest Peter Jones and ex-Dragon Theo Paphitis.

William, who has been the royal patron of the UK-based charity since 2005, marked its 25th anniversary with a speech.

William and Joss Stone pictured at the Tusk Trust ball

"The need to protect wildlife in Africa is greater than ever before. You'd have thought we learnt the lessons years ago in the great campaigns to 'Save the Whale' or 'Save the Polar Bear'. But sadly we haven't," said the royal.

"The elephant and the rhino, among others, are going the same way and, unbelievably, will be extinct in the wild within a few decades, or even less."

He added: "The illegal slaughter of elephants and rhino for their horns is barbaric, and it's not stylish to be associated with it."

Kate debuted a new look at her engagement earlier that day

William, 33, has supported the charity privately and publicly on many occasions – he visited Tusk projects in Botswana in 2010 with his brother Prince Harry, and launched the Tusk Conservation Awards three years later.

Earlier this month, he paid tribute to a Kenyan wildlife ranger in recognition of his "extraordinary contribution" to the cause.

His intervention came after Edward Ndiritu, the head of the anti-poaching unit at the Lewa Conservancy in northern Kenya, became the first winner of the Tusk Trust's Wildlife Ranger Award – an award instigated by the Prince to recognise the perilous work of those on the frontline of conservation.