Jon Anderson is suffering from respiratory problems, prompting Yes to cancel its summer tour.

The 63-year-old singer, who’s since been diagnosed with acute respiratory failure, was ordered by doctors last weekend to rest for at least six months “or suffer further health complications,” it was announced Wednesday in a statement released by representatives for the band and Live Nation, which was presenting the tour.

That means no hitting the road for Anderson, who was to kick off the band’s 26-city summer tour in Quebec on July 12.

“I’d like everyone (to) know how deeply disappointed I am by this turn of events,” Anderson said in a statement. “I was looking forward to celebrating our music with the amazing family of Yes fans once again; but as we all know, health must come before anything else.”

Bassist Chris Squire, who formed Yes with Anderson in 1968, said Anderson’s health was the band’s primary concern, though he was “especially regretful of the fact that … many of our fans and friends have probably laid out nonrefundable airfares and hotels, etc., in order to enjoy the Yes shows this summer.”

Ticket refunds are available at point of purchase.

The tour, called “Close to the Edge and Back,” the band’s first outing in four years, included concerts in Toronto, Chicago, Detroit, Boston, Miami, Atlanta and Seattle. It was to close in Universal City, California, on August 22.

Anderson and Squire were to be joined by guitarist Steve Howe, drummer Alan White and Oliver Wakeman on keyboards. Wakeman’s father is former Yes keyboardist Rick Wakeman.

The band, whose hits include “I’ve Seen All Good People,” “Roundabout” and “Owner of a Lonely Heart,” previously released the album “Magnification” in 2001.