U.S. President Donald Trump voiced hopes Wednesday of a successful planned summit with North Korean leader Kim Jong Un but warned that he could "respectfully" walk away if it appeared the talks would not be "fruitful."

Trump delivered his remarks during a news conference with Prime Minister Shinzo Abe at the president's Mar-a-Lago estate in Florida, where he touted the progress made in grappling with the North Korean nuclear issue.

The odds of the U.S.-North Korean summit happening ticked up several notches a day earlier when he announced that his CIA chief had visited the isolated North for face-to-face talks with Kim earlier this month as part of planning for what would be the first-ever meeting of a sitting American president and North Korean leader.