Prince Harry welcomes Kate to the Royal Family

Harry, 26, said he was "delighted" Prince William had "finally popped the question" and that now he would gain a "sister" – something he says he has always wanted.

The Prince's comments were made during an interview with the German newspaper Bild and came ahead of his visit to Berlin today to receive an award recognising his charity work.

He will be presented with a Golden Heart on live television during Ein Herz fur Kinder – A Heart for Children – Germany's largest television fundraising gala.

Speaking about William's engagement to Kate, Harry said: "I'm absolutely delighted that he's finally popped the question. We all are.

"I've always wanted a sister and now I've got one. I've known Kate for years, and it's fantastic that she is becoming part of the family."

Harry is making his first trip to Berlin but said he had been to Germany twice before.

He said: "I know the German people are always very welcoming so I'm looking forward to meeting Berliners ... as long as nobody mentions anything about the football."

The Prince also spoke about the influence his mother Diana, Princess of Wales and father, the Prince of Wales, have had on his charity work.

He said: "My mother was an inspiration to me, and my brother. And also to so many people around the world.

"She did so much fantastic work with her charities and I think people particularly warmed to her because of the way she was able to put them at ease, no matter what environment or situation they were in.

"Her compassion was obvious to see. Like her, I realise I am in a privileged position as a member of the Royal Family, and I have to use what I have been given to highlight important issues."

Harry is patron of several children's and humanitarian charities.