Democrat frontrunner Joe Biden has been scrambling and reportedly called fellow contender Sen. Cory Booker (D-NJ) to clear the air over Biden’s glowing remarks on late segregationist Sens. James Eastland (D-MS) and Herman Talmadge (D-GA) Thursday.

The two spoke on the phone 15–20 minutes following the fallout over what Booker calls Biden’s “hurtful” and “harmful” remarks.

Booker spoke to MSNBC’s Lawrence O’Donnell and talked about the call, but he did not provide explicit details of the conversation.

“I don’t want to characterize a private conversation,” Booker said, noting that it was “constructive.”

Booker said he used the call as an opportunity to tell Biden why it was offensive to joke about Eastland calling him “son” instead of “boy,” explaining that it was an indication that he –Eastland – saw himself in Biden.

“That’s the kind of dialogue I think is a constructive thing,” Booker said.

While Booker said he felt better “understood” by Biden after the phone call, he did not retract his call for Biden to apologize and added that he knew what Biden’s intentions were before the phone call took place.

“I understood where his intentions were. I understood where his heart was. The fact is, though, it’s not about me or him. He said things that are hurtful and are harmful,” Booker said.

“I believe he should be apologizing to the American people and having this discussion with all of us,” he continued.

Booker said he waited almost an entire day for Biden to “speak to these issues,” and he did not.

“That’s why I felt the need to speak out,” Booker said.

Politico, citing to two sources familiar with the call, described Biden’s scramble as a flop, saying:

Biden’s campaign had sent talking points to surrogates that highlighted the vice president’s work on civil rights and noted that Biden’s opponents had worked with officials who might be considered lightning rods to Democrats, including former Attorney General Jeff Sessions — a move that further inflamed the situation.

“I find it remarkable that the surrogate talking points they were sending around, as they were trying to contain this, include no mention of the language the vice president used and instead tried to spin that the vice president is being criticized for working with people he disagreed with,” a Booker aide said. “That’s nonsense and speaks volumes to what they know is true, which is, he should be apologizing for what he said.”

Booker’s campaign spokeswoman, Sabrina Singh, confirmed the conversation and reaffirmed Booker’s previous calls for Biden to apologize, saying:

Cory shared directly what he said publicly — including helping Vice President Biden understand why the word ‘boy’ is painful to so many. Cory believes that Vice President Biden should take responsibility for what he said and apologize to those who were hurt.

The political firestorm began at a fundraiser at the Carlyle Hotel in New York City on Tuesday, with Biden using his ability to work with segregationists as an example of his ability to lead.

“I was in a caucus with James O. Eastland,” Biden said. “He never called me boy, he always called me son.”

“Well guess what?” he continued. “At least there was some civility. We got things done. We didn’t agree on much of anything. We got things done. We got it finished.”

“But today you look at the other side and you’re the enemy,” he added. “Not the opposition, the enemy. We don’t talk to each other anymore.”

It remains unclear why Biden used Eastland and Talmadge to point to his ability to reach across the aisle, as they were both Democrats.

“You don’t joke about calling black men ‘boys.’ Men like James O. Eastland used words like that, and the racist policies that accompanied them, to perpetuate white supremacy and strip black Americans of our very humanity,” Booker’s statement said in part.

“I have to tell Vice President Biden, as someone I respect, that he is wrong for using his relationships with Eastland and Talmadge as examples of how to bring our country together,” he continued.

“Frankly, I’m disappointed that he hasn’t issued an immediate apology for the pain his words are dredging up for many Americans,” Booker added. “He should.”

Biden remained defiant, telling reporters that Booker “knows better” and should apologize.

“Cory should apologize. He knows better,” Biden said. “There’s not a racist bone in my body. I’ve been involved in civil rights my whole career, period, period, period.”

As of Friday morning, Biden still had not issued an apology.