Pop veteran Elton John believes that Lady Gaga will reign as the 'Queen of Pop' in the years to come as she is grounded and respectful. The 'Rocket Man' hitmaker first teamed up with the 24-year-old pop star for a performance at the Grammy Awards last year and recently recorded a duet for his latest movie project,'Gnomeo and Juliet'. Since then they have become close friends and John is convinced that the 'Poker Face' hitmaker will have a long career as she is so modest,Contactmusic reported. "I love her,she's absolutely amazing. We've become friends. What I like about the Gaga most is that she's amazingly polite and respectful to everyone around her. What I loved most about John Lennon is that he was like that. He once gave my mum a lift to the airport and came to my agent's wedding," said the 63-year-old singer. "The Gaga is like that. But the greatest thing about her is that she manages to let everyone think they know everything about her but no one knows anything," he said. "She's a phenomenal star,definitely someone who will be taking on the old sods like me,McCartney and Rod Stewart doing big tours for years to come. Pure genius," he added.