NEW YORK, N.Y. – Guitarist Bob Weir is cancelling all of the tour dates he had planned through January.

The Grateful Dead founder says his tour with his other band, RatDog, won’t kick off this week as planned. He posted a message Sunday on RatDog’s website saying “circumstances have necessitated that all scheduled tour dates for Bob Weir & RatDog are being cancelled.”

The 66-year-old didn’t offer more details. An agent for Weir didn’t respond to an email seeking comment.

Refunds can be claimed where tickets were purchased.

Weir also is cancelling a September performance at the Lockn’ Festival with Furthur, the band he formed with fellow Grateful Dead member Phil Lesh.

Weir fell onstage at a concert last year. Lesh told the crowd that Weir had been suffering from a strained shoulder.