One day after postponing four performances of his one-man show “Weapons of Self-Destruction” due to shortness of breath, Robin Williams was forced to postpone the remainder of his 80-city tour until the fall to undergo surgery for an aortic valve replacement.

“I’m so touched by everyone’s support and well wishes,” said Williams in a statement. “This tour has been amazing fun and I can’t wait to get back out on the road after a little tune-up.”

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Previously purchased tickets will be honored once the new dates are scheduled or ticket holders can contact their place of purchase to inquire about refund policies.

However, the eight concerts scheduled for New York City’s Neil Simon Theatre might find the venue unavailable if a Broadway show moves in. In that case, another venue could be used, but ticket holders would probably have to exchange their tickets for the new configuration. Those shows are presented by James L. Nederlander and Ron Delsener

Williams has been on the sold-out “Weapons of Self-Destruction” comedy tour since September 2008.