Willie Nelson has canceled his upcoming tour dates due to a medical issue. The news came straight from the country icon himself, on Twitter, late Wednesday (Aug. 7) night.

"To my fans, I’m sorry to cancel my tour, but I have a breathing problem that I need to have my doctor check out," Nelson tweeted. "I’ll be back. Love, Willie."

To The Boot, Nelson's publicist clarifies that the country star has canceled his six remaining August shows, which also were to feature Alison Krauss. Those shows were scheduled for Aug. 9 in Grand Rapids, Mich.; Aug. 10 in Huntington, W.V.; Aug. 12 in Florence, S.C.; Aug. 14 in Charlottesville, Va.; Aug. 16 in Greenville, S.C.; and Aug. 17 in Greensboro, N.C. Nelson will resume his time on the road in September.

Nelson, who turned 86 at the end of April, keeps an extensive tour schedule. His 2019 calendar is filled with a September string of Outlaw Music Festival Tour stops, an October Las Vegas residency and additional shows through November. Nelson is also scheduled to perform at Farm Aid 2019 in September.

Nelson has canceled shows due to breathing troubles before, most recently in early 2018, but as far back as 2012. He's dealt with emphysema and pneumonia on a recurring basis, even undergoing a stem cell operation to help his lungs in 2015.

From time to time, Nelson has been the victim of a death hoax; in 2017, when rumors of his impeding demise began swirling after he canceled some concerts due to illness, his publicist even stepped in to address the false reports. Nelson himself pokes fun at the recurring hoaxes and rumors with his song "Still Not Dead," released in 2017.

In addition to keeping himself on the road, Nelson has continued to release new music. His most recent album, Ride Me Back Home, arrived in June.

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