Prince William, Kate Middleton and Prince Harry inspire London Marathon 2017 runners

British royalty dominated the Virgin Money London Marathon as Prince William fronted ceremonial proceedings alongside wife Kate Middleton, the Duchess of Cambridge and younger brother Prince Harry, on Sunday (23 April).

The trio launched the event by pushing a buzzer at the start of the 26.3 miles race, with more than 39,000 runners competing overall.

Dressed in all black, the royals attire featured the logo of Heads Together – the mental health charity which they are supporting for the marathon.

After greeting runners and beginning the race, William, formally known as the Duke of Cambridge, appeared in high spirits as he joined Middleton to toot red horns encouraging runners.

The couple then joined Prince Harry, who is the Patron of the London Marathon Charitable Trust, to make the official presentations to winners of the elite men, women and wheelchair races.

Victorious competitors included Kenyan runner Mary Keitany, who set a new women's only world record by crossing the finish line in 2:17:01.

Her fellow countryman Daniel Wanjiru won his first ever London Marathon, beating overwhelming favourite, Kenenisa Bekele.

In the wheelchair race category, British paralympic hero David Weir set a record of seven London Marathon victories.

The feat saw the 37-year-old surpass Tanni Grey-Thompson's record of six, as he beat Switzerland's Marcel Hug on the line to clinch gold.

Prince Harry is also set to meet civilian winners with his fellow royals. The appearance marks a culmination of a number of public appearances to discuss their work for mental health charity Heads Together, as the monarchy's next generation make a concerted effort to tackle the stigma around related conditions.

Earlier this week, the family members spoke candidly in a Facebook Live video about the mental health struggles they have faced in their own lives – particularly pertinent to Prince William and Prince Harry, who lost their mother, Princess Diana in a Paris car crash in 1997.

Filmed as part of the #Oktosay series the brother's opened up about the impact of losing their mother at such a young age, 15 and 12 respectively.

"Both of us have always been open to each other, but we've never really talked about it. We've never really talked about losing a mum at such a young age," said Prince Harry during the film.

"You then when you speak to other people's families and little kids, you think 'wow I don't want them to have to go through the same things'. You want to with a little bit of experience, you want to help as much as you can and try to empower them to have that conversation. You want it to be brave for themselves to talk about it at a young age rather than bottling it up for far too long."

The video came days after the third-in-line to the film gave an emotional interview to The Telegraph, detailing the deep-rooted emotional impact the loss had on his life, and how he sought therapy to cope.