Country music icon Willie Nelson blamed the altitude after he left the stage early with "breathing problems" during a concert Sunday night near Salt Lake City, Billboard reports.

Nelson, 84, apologized to fans in a statement provided to Variety.

"This is Willie. I am very sorry to have to cut the Salt Lake City performance short tonight," the statement read. "The altitude just got to me. I am feeling a lot better now and headed for lower ground."

Early Monday, the singer tweeted a similar message from his verified account.

>> See the tweet here

The venue, USANA Amphitheatre, is in West Valley City, Utah, which is more than 4,300 feet above sea level, Variety reported.

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