Marco Rubio: Donald Trump Is Not 'Ready' to Be President

VIDEO: Rubio Says Trump Has Touched a Nerve, But That Doesnt Mean Hes Should Be PresidentPlayABCNews.com
WATCH Rubio Says Trump Has 'Touched a Nerve,' But That Doesn't Mean He's Should Be President

Marco Rubio has largely avoided saying what he thinks of Republican front-runner Donald Trump. But when he sat down at Ron Morrison’s table at a diner in Manchester, New Hampshire, Morrison pressed him for a straight answer.

“I don’t think he’s ready to be president of the United States,” Rubio conceded.

In September, the Florida senator said that Trump hadn’t come up with any “serious” policy proposals, but that there was still time for him to do so. Now, with less than two weeks until the Iowa caucuses, it would appear Rubio has changed his mind.

“We have a right to be angry and upset about the direction of our country,” said Rubio. “But that alone won’t be enough. You gotta know what you’re going to do about it.”

He continued: "We owe it to you to tell you exactly what we’re gonna do. And it can’t just be, 'Oh we’re gonna make everything great again.'"

As the conversation wrapped up, one of the diners was curious to know what Rubio thought of Sarah Palin's endorsement of Trump earlier this week.

“I like Sarah Palin. She doesn’t always say nice things about me, but I like her very much,” Rubio answered.

"Oh say it — 'she’s an idiot,'" one of the diners pushed.

Rubio refused to take the bait.

“No, I don’t believe that, I don’t believe that at all,” he said, adding that he had never met her. “I love her spunk and her energy.”