Celebrations for the coronation of King Charles continue with a special concert at Windsor Castle tonight. However, not everyone was keen to get involved, with some major stars said to have opted out of the event. The coronation concert will be headlined by stars including Katy Perry, Lionel Ritchie and Take That, but there are reportedly a number of A-list celebrities who turned down the chance to perform. Around 20,000 members of the public will attend the concert, along with celebrities and members of the royal family. It is the first ever concert event to take place at Windsor Castle and is part of three days worth of celebrations following the crowning of the King and Queen. The coronation ceremony saw King Charles and Queen Camilla crowned inside Westminster Abbey yesterday (May 6). The concert will be broadcast live on BBC1, BBC iPlayer and BBC Sounds at 8pm. It will be hosted by BBC radio 2 presenters Dermot O’leary and Scott Mills, after Zoe Ball pulled out due to illness. According to Rolling Stone magazine, Harry Styles was offered the chance to perform at the concert, but turned down the offer. No reason was given as to why the former One Direction star said no to the opportunity. Sir Elton John has close ties to the royal family, famously performing at the funeral of Princess Diana in 1997. However the ‘Rocket Man’ singer turned down the coronation concert due to scheduling conflicts. Despite initial rumours the Spice Girls would reunite for the coronation concert, Rolling Stone reported the group passed on the opportunity. Adele is another star who turned down the chance to perform at the special concert - with no reason given for her decision. While Take That will perform in front of King Charles for the coronation concert, Robbie Williams turned down the chance to reunite with his former bandmates. Kylie Minogue was reportedly asked to perform at the concert, but turned it down after considering the growing republican sentiment in Australia. Organisers were reportedly keen to get Ed Sheeran involved in the concert, but the singer was unable to make it due to his busy schedule. As well as the one-off performance from the Royal Ballet, The Royal Opera, The Royal Shakespeare Company, The Royal College of Music and The Royal College of Art, the following artists will be performing and appearing. Bollywood star Sonam Kapoor will also deliver a spoken word performance.