After months of speculation, the 33-year-old has decided to return the favour after Harry served as best man at the Duke and Duchess of Cambridge’s 2011 nuptials.
According to Kensington Palace, Prince William is ‘honoured’ to have been given the role and is ‘very much looking forward to supporting his brother’ at the May 19 ceremony.
On Thursday, the brothers visited Greenhouse Centre charity in London and reporters asked how the Duke of Cambridge felt after being asked to take on the top job.
“It feels great,” Prince William replied. “[I’m] thrilled and delighted, honestly.”
And it wouldn’t be William without a quick tease, as he added: “Revenge is sweet.”
Prince Harry also took the opportunity to clarify that the decision wasn’t a last minute call, as he has ‘known for months’. Before he joked: “I got down on one knee.”
But who else was in the running for the coveted job?
Harry has been friends with Tom Inskip ever since they studied together at Eton and he even brought Meghan Markle as his date to Inskip’s Jamaican wedding to Lara Hughes-Young.
It’s also surprising to learn that he has not asked London bar owner and fellow party goer for many years, Guy Pelly.
Harry and Meghan have a 600-strong guest list for the chapel ceremony and over 2,640 guests have been invited to the grounds of Windsor Castle (1,200 of which are members of the public) to participate in the pomp and pageantry.
After saying their ‘I dos’, close friends and family will gather at Frogmore House for a celebratory evening hosted by Prince Charles.
Harry and Meghan will tie the knot at St George’s Chapel in Windsor on May 19.
Scroll to see the the best photos of Harry and Wills from over the years, proving that William’s always been Harry’s best man.
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