Elton John has pneumonia, and it’s unclear if he’ll continue what he says is his final world tour.

“I played and sang my heart out, until my voice could sing no more,” he said in a tweet. “I’m disappointed, deeply upset and sorry. I gave it all I had.”

John, 72, abruptly left the stage during Sunday’s concert in Auckland and returned minutes later for two more songs before saying, “I’ve just completely lost my voice. I can’t sing. I’ve got to go. I’m sorry,” the BBC reports.

Earlier in the set he told the sold-out crowd he’d been diagnosed with walking pneumonia.

He’s scheduled to play two more concerts in Auckland on Feb. 18 and 20, followed by shows in Australia, as part of his “Farewell Yellow Brick Road” world tour.

John thanked his fans Sunday on Twitter.

The flamboyant superstar took home his first Oscar in 25 years this year for “Rocketman,” which won for best original song. He won previously for “Can You Feel the Love Tonight?” in 1995.

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