President Donald Trump said Thursday he thinks he’s "very well prepared" for his summit meeting with North Korean dictator Kim Jong Un but said the meeting is more about "attitude" than it is a matter of preparation.

“I think I'm very well-prepared. I don’t think I have to prepare very much. It's about attitude, it's about willingness to get things done. But I think I have been prepared for this summit for a very long time,” Trump said in the Oval Office when asked by a reporter what he’s doing to prepare for the June 12 meeting in Singapore.

Trump made the comment sitting next to Japan's Prime Minister Shinzo Abe who was in Washington to discuss the summit.

The president added that the North Koreans are also prepared: “I think they’ve been preparing for a long time, also. So this isn’t a question of preparation, it’s a question of whether or not people want it to happen, and we’ll know that very quickly.”

Even as the president said that the summit is “all ready to go” he also qualified that everything is “subject always to change you never know in this world, subject to change.”

The president also the summit will be “much more than a photo op.” While he again reemphasized that the meeting will likely not produce a firm deal, he said it will be the start of “perhaps a good relationship” as a starting point to an ultimate deal.

“Well, it's going to be much more their photo op. I think it’s a process. I’ve you that many times before. I think it's not a one-meeting deal. It would be wonderful if it were,” Trump said. “This will not be just a photo op. This will be at a minimum, we'll start with perhaps a good relationship and that's something that is very important towards the ultimate making of the deal. I'd love to say it could happen in one deal. Maybe it can.”

Trump also reiterated that the U.S. will accept nothing less of denuclearization, though he didn't define the terms of denuclearization.

“They have to denuke. If they don't denuclearize, it will not be acceptable. We cannot take sanctions off,” he said.

He also made reference to his previous golf game with Shinzo Abe in Japan, noting that they went golfing with famed Japanese pro-golfer Hideki Matsuyama, who Trump said is the number two celebrity in Japan next to Abe, who he said is the number one celebrity.