This A-list celebrity might be the first to turn down an invite to the royal wedding

And everyone’s surprised.

Prince Harry and Meghan Markle’s wedding is less than a month away, with the couple set to tie the knot on May 19th at St George’s Chapel at Windsor Castle.

With the nuptials fast approaching, speculation is building around every aspect of the royal wedding day, from Meghan Markle’s wedding dress designer to who will be giving speeches at the reception.

Now that the bridal party has reportedly been confirmed - with it only announced last week that Prince William would be his brother’s best man, the focus has turned to the guest list, with a host of famous faces expected to be in attendance.

The Duke and Duchess of Cambridge’s ceremony boasted a star-studded guest list, from Victoria and David Beckham to Ellie Goulding. But with 33-year-old Harry running in celebrity circles and Meghan being a former Hollywood actress, their wedding guest list is set to be even more impressive, with the Beckhams, Priyanka Chopra and Elton John rumoured to be in attendance.

One A-list celebrity hinted that she might be turning down the invite however, with Grand Slam champion Serena Williams opening up about the wedding in a recent interview on Good Morning America.

Despite being a close friend of the bride, the tennis star explained about how the wedding might actually clash with work, telling the Good Morning America presenters that she was unsure if she would be able to attend.

‘I don’t know,’ she explained when asked if she’d be at the royal wedding. ‘I think it’s during one of the tournaments, I’ll see if I can make it.’

‘I’m obviously super happy for her,’ Williams explained of her friend. ‘She’s such a great girl and she is incredibly nice and I couldn’t be happier for her.’

Going on to impart some advice from her own wedding, she continued: ‘I just think it’s so important to enjoy the moment. And eat the cake - I didn’t get to eat mine at the wedding. We were just having so much fun.’

If there's one thing we can rely on, it's that the royal wedding is definitely going to be fun.