Sir Elton John admires Kate Middleton for 'going through' with her marriage to Prince William

The 'Rocket Man' singer will attend the couple's nuptials at Westminster Abbey in London on Friday (29.04.11) and although Elton believes the prince's mother Diana – who died in a Paris car crash in 1997 – would love the bride, he admitted Kate and William are in for a "bumpy ride".

He said: "I hope everyone celebrates for them, whether they agree with the monarchy or not. It's about two people falling in love and getting into a situation, for her especially, where it's going to be the most difficult life. I mean, let's face it, we know what that kind of marriage entails, and the press never leave you alone, the courtiers ... I admire her for going through with it.

"I've only met William and Harry twice … but I'm very glad to be invited because I think it's going to be a very joyous day and I think [Diana] would be very happy with his choice, [Kate] seems such a great girl and they seem so much in love."

Elton performed at the funeral of Princess Diana in Westminster Abbey in 1997 and he believes William's choice to hold his wedding at the same venue is the most "joyous result".

In an interview with on 'Good Morning America' with Barbara Walters, he said: "My heart sank when I saw those two boys walking behind the coffin. I thought that was the hardest thing, I can't imagine at that young age having to walk in the public, following your mother's coffin. And the next time we're in the Abbey it's to see him walking up the aisle with a beautiful woman, the love of his life, I think it's the most joyous result and I'm sure Diana would be very, very happy about it."