George Takei and William Shatner did not get along on "Star Trek," and they don't get along now.

Last week, George Takei was on an episode of "Real Time with Bill Maher," and he let everyone know why he continues to dislike William Shatner, notes the New York Post.

"Canadians have a certain image of being even-tempered and friendly and all that," he said. "Well, he is a person who is that way with himself. He is very self-centered."

Takei said that the two are human, but they tried to remain professional on set of the show. There was some difficulty, though.

He also said that most of his co-stars knew he was gay, and they were "cool" about it. They didn't try to out him because they knew that would ruin his career, but one person didn't know.

"It went right over his head," Takei said about Shatner. "He was the only one that didn't know."

The two have previously commented on their relationships.

For example, Shatner said that he didn't know Takei very well, as his role was small. But he also complained that he wasn't invited to Takei's 2008 wedding.

"There must be something else inside George that is festering, and it makes him so unhappy that he takes it out on me, in effect a total stranger," Shatner said. "Why would he go out of his way to denigrate me? It's sad, I feel nothing but pity for him."

Takei tells a different story. He said that he did invite Shatner, but he never heard back.

Takei has said that when filming "Star Trek," Shatner would tell the director to focus on him instead of whoever was speaking because his reactions were important.

In 2008, Shatner said that he did not harbor any hard feelings toward Takei.

"George has been mean to me for a long time," he said. "I mean, decades and decades. I've never said anything. He continues to be mean and I don't know why."