(Photo credit: Raymond Flotat)

Iconic R&B vocalist D’Angelo has pulled out of a tribute concert to three-time Grammy Award-winning singer-songwriter Bill Withers, citing an unspecified medical concern.

D’Angelo’s label, RCA, announced on Wednesday that the singer would no longer be attending or performing at Withers’ Carnegie Hall tribute on Thursday October 1, 2015. The release, as cited by The New York Times, states that he has withdrawn from the performance “following doctor’s orders.”

Additionally, The New York Times notes that a further statement by D’Angelo’s doctor, Ronald Primas, did not specify the underlying problem. But, the singer was treated on Tuesday and had been advised to “to refrain from any strenuous activity for the next two weeks,” according to The New York Times’ citation of the doctor’s statement.

In the RCA release, D’Angelo was “disappointed at missing an opportunity to pay homage to Mr. Withers, who he considers ‘a true legend and inspiration to me and my entire generation of artists.’”

And, for his part, Withers’ issued a statement that said, “Aw man, hope D’Angelo recovers quickly from whatever malady has befallen on him. I will miss his version of ‘Use Me.’ I was so looking forward to seeing him throw down with the super band that Greg Phillinganes put together for this event. Come on, D’Angelo! Get well, buddy!”

The tribute concert will recreate Withers’ Live At Carnegie Hall album, which was originally released in 1973, along with a number of other songs from his musical career. A few of the featured artists are singer-songwriter Ed Sheeran, former Doobie Brother Michael McDonald, folk and soul singer-songwriter Amos Lee, award-winning jazz vocalist Gregory Porter, along with country singer Kathy Mattea – who is from Withers’ home state of West Virginia, and Withers’ daughter, Kori, who has gone on to pursue her own musical career.

Apart from the tribute performance, D’Angelo has also pulled out of the Atlanta iteration of the Afropunk Festival, according to SPIN. However, he will not be missing out on the excitement, since the entire festival has been cancelled “amidst an ongoing and increasingly poor weather outlook for the greater Atlanta area.” Read the festival organizers’ full statement, here, and note that all tickets for Afropunk Atlanta will automatically be refunded from their point of purchase.