Harry Styles, Adele, Ed Sheeran, singers decline to perform at King Charles III's coronation

MANILA, Philippines — The coronation of Britain's King Charles III this May has promised to include a star-studded concert, however, celebrities don't appear keen to be part of the celebrations.

At the top of Charles' wishlist to perform were award-winning singers Adele and Ed Sheeran, but both declined the invitations as they were unavailable.

Sheeran said he did so because of logistics and his ongoing "+–=÷×" world tour. Additionally, the release of his upcoming album "-" (Subtract) will be the day before the coronation itself.

Another big name that turned down a chance to perform is this year's Album of the Year winner Harry Styles, although his ongoing "Love On Tour" has no dates between his second night in Tokyo on March 25 and his first night in Denmark on May 14.

Related: King Charles III coronation: Processions, concert, Prince Harry? What to expect

Elton John, a close friend of Charles' ex-wife the late Princess Diana, also unsuprisingly declined to perform as he too is on tour, his last one ever in fact.

Buckingham Palace even attempted to reunite the Spice Girls for the coronation concert, but was unsuccessful.

Those who have confirmed so far are Andrew Lloyd Webber, Lionel Richie, Kylie Minogue and her sister Dannii. Olly Murs is trying to free up time so he could attend.

This will be Great Britain's first coronation in 70 years, when Charles' mother Elizabeth II was crowned in 1953. The queen passed away in September last year, with Charles immediately ascending to the throne.

Several thousand pairs of tickets for the coronation concert at Windsor Castle will be made available through a public ballot, while volunteers from charities supported by Charles and his wife Camilla will also be able to attend.

RELATED: UK's Camilla to wear Queen Mary's Crown at May coronation