Alicia Keys on the most important phone call she had with Prince

A host of celebrities from Mariah Carey to Justin Timberlake have paid tribute to Prince since his sudden death on April 21, and GRAMMY winner Alicia Keys joined the pack at a party that night. The singer reminisced about the music icon while celebrating her film The Gospel at New York City's Highline Ballroom.

The 35-year-old began the night by telling party-goers that the day was "heavy" and "shocking." News of the "Purple Rain" singer's death had broken hours before the Tribeca Film Festival event. "We have lost one of the most prolific artists of our time," Alicia said. "He showed me what it is to be an artist."

TAP FOR FULL GALLERY Photo: Jamie McCarthy/Getty Images for Tribeca Film Festival

After screening her short film and a project shedding light on the refugee crisis, Alicia performed an array of old and new music, including a Prince cover. But prior to honoring the musician with a rendition of his "How Come U Don't Call Me Anymore?"Alicia recalled the first time she spoke with the legendary singer, asking for permission to include his song on her album.

"I felt nervous in a way I had never felt nervous before," she admitted to the crowd. At around age 19 and on her very first tour, she waited for Prince's phone call in a hotel room, which sounds easier said than done.

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Alicia revealed that she was transferred to about eight people as her nerves were "building" before she was finally on the line with the man himself. In the end, the iconic singer gave her permission to record the song — something she admitted Prince hadn't done before.

"[It's been] incredible to know him as much as one can know Prince, which is really at least 8 people in between," Alicia jokingly said.

She added, "He was the absolute greatest ever."

Photo: KMazur/WireImage

Back in 2004, Alicia delivered the induction speech for Prince's Rock and Roll Hall of Fame ceremony. After learning of his death on April 21, the "Karma"singer penned a moving message for the seven-time Grammy winner on her website.

"Prince was a gift, a genius and a reminder that we have no limits," she wrote. "The power in his songs moved me always. His music left me changed forever. I’ve said this before and I’ll say it again, there is only one Prince."

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