Democratic presidential candidate Bernie Sanders is making the west coast late-night rounds ahead of California’s primary, stopping by “Real Time with Bill Maher” last night for a one-on-one interview.

Maher mentioned the great missed opportunity that was Sanders’ rumored debate with GOP nominee Donald Trump, who backed out on Friday.

After making guttural noises, Sanders said he “would have loved” to debate Trump.

“First he said he would do it. Then he said he wouldn’t do it. Then he said he would do it. Then he said he wouldn’t do it,” Sanders explained. “So, I would hope that if he changed his mind four times in two days, change it a fifth time.”

“Trump claims to be a real tough guy,” he continued. “He pushes people around. Hey, Donald, come on up, let’s have a debate about the future of America.”

Watch the full interview below: