Prince and Princess of Wales pictured rehearsing for Earthshot awards ceremony in Boston

The Prince of Wales during rehearsals for the Earthshot Awards at MGM Music Hall at Fenway in Boston Credit: PA Wire/PA Images

The Prince and Princess of Wales have arrived at rehearsals for the Earthshot Prize ahead of its star-studded ceremony in Boston on Friday evening.

Singer Billie Eilish will lead a stellar entertainment line-up during a ceremony – dubbed Prince William's “world cup” moment – that aims to raise environmental awareness.

Former England and Manchester United footballer David Beckham will present one of the five awards, with each category winner receiving £1 million to develop their project.

Kate pictured during rehearsals for Earthshot Credit: Chris Jackson/PA

The prince is due to meet US President Joe Biden ahead of the event at the MGM Music Hall.

The couple’s three-day trip to Boston has been overshadowed by the race row that saw William’s godmother Lady Susan Hussey resign as a royal aide after she repeatedly questioned a prominent black British-born domestic abuse charity boss about where she “really came from”.

The timing of a trailer promoting the Duke and Duchess of Sussex’s Netflix docuseries, released on William and Kate's second day in the States, raised eyebrows among some royal commentators who interpreted it as a snub to the Prince and Princess of Wales.

Prince and Princess of Wales arrive in Boston for Earthshot awards
Date set for Prince Harry's bombshell memoir, 'Spare'

In a black-and-white image released of Kate she is seen in silhouette walking across the stage of the theatre as an image of a cloud-filled sky is projected behind the royal.

In another image William is photographed laughing as he chats to someone off camera with broadcast equipment in the background of the picture.

The Prince and Princess of Wales made a three-day visit to Boston this year. Credit: Chris Jackson/PA

Organisers of Earthshot have implemented a number of green policies, from encouraging guests to dress sustainably, from wearing vintage clothing or recycling outfits for future use, to ensuring the plants and flowers on display are grown locally.

Celebrities will walk a green not red carpet, the same used for last year’s inaugural ceremony, and it will be recycled after the event, make-up used will be predominantly vegan or certified cruelty free and all the food served will be plant-based.

Listen to the ITV News Royal Rota podcast