Biden was asked if he will be able to deal with Russia's Vladimir Putin and China's Xi Jinping in two or three years from now, should he be reelected.

"I'm ready to deal with them now and three years from now," he said.

He said he is dealing with Xi right now and that he has "no good reason" to speak with Putin right now.

"There isn't any world leader I'm not prepared to deal with," Biden said.

The president responded to a question about whether European allies should prepare for U.S. disengagement if Trump wins by contending that he has their support in the U.S. election.

"I'm not hearing my European allies coming up to me and saying, 'Joe, don't run,'" he said. "What I hear them saying is, 'You've got to win. Don't let this guy -- it would be a disaster.'"

Biden pointed out Trump has an "affinity to people who are authoritarian."

"That worries Europe. That worries Poland," he said.

Biden said he needs to "pace himself" when pressed on how he is up to the 24/7 nature of the presidency -- while taking a crack at Trump's schedule compared to his own.

"Where has Trump been? Riding on his golf cart and filling out his scorecard?" Biden said. "He has done virtually nothing. I've had roughly 20 major events, some with thousands of people showing up."

Biden said he has always had an inclination to "keep going" but "I just have to pace myself a little more."

"In the next debate, I'm not going to be traveling in 15 time zones the week before," he said.

Biden addressed his previous statements that Vice President Kamala Harris "would be ready on Day One."

The president touted Harris' work with women's reproductive health issues and her time in the Senate.

"I wouldn't have picked her unless I thought she was qualified to be president. From the very beginning, I made no bones about that. She is qualified to be president. That's why I picked her," he said.