Actor and marijuana activist Tommy Chong took to social media to vent after he was apparently disinvited from introducing Democratic presidential candidate Bernie Sanders at a rally in Los Angeles on Monday.

The 77-year-old Cheech and Chong star was set to introduce Sanders at a rally in East Los Angeles Monday afternoon but was apparently snubbed by the campaign just a few hours before the event was scheduled to begin.

Chong took to Twitter to explain the situation to his followers:

“I have done lots of campaigning for Bernie, his causes, and the messaging his campaign staff has either emailed or contacted me directly on,” Chong wrote. “Unfortunately after months of support and endorsement videos, I have to report that @BernieSanders pulled away his invite to me.”

He later called the cancellation “an insult” in a follow-up interview with the Hollywood Reporter.

“It’s lip service to get the votes, but they don’t want to endorse what I stand for and what I’ve stood for all my professional career,” Chong told the outlet.

While the actor-comedian initially appeared to be disappointed in the sudden cancellation, he returned to Twitter a short time later to report that there had been a scheduling conflict with the Sanders campaign and that he would resume his activism on behalf of the candidate.

“Hope to continue my support, reschedule, and continue activism, political change and promoting peace anywhere possible,” he wrote.

Chong cut a public service announcement for the Sanders campaign in February in which he compared the Democratic socialist Vermont senator to high-grade marijuana.

“Bernie’s like a kush, the best kind of weed you can get, because he’s the answer to all our problems,” he told CNN at the time.

Chong also had harsh words for presumptive GOP nominee Donald Trump in a separate interview in February, telling The Hill that Trump represents the Republican Party’s “karma.”

“What Trump did, he sort of exposed the inner workings of the Republican mindset, and they can never put that genie back in the bottle, try as they may,” he said.

Follow Daniel Nussbaum on Twitter: @dznussbaum.