President Trump and Shinzo Abe
Susan Walsh, AP

WASHINGTON – President Trump said Thursday he's ready for his close-up with North Korea's Kim Jong Un, even though "I don’t think I have to prepare very much" for next week's session in Singapore — and he might invite Kim to the White House if things go well.

Exuding optimism, Trump said a nuclear weapons agreement with North Korea would require more than one meeting, but striking it could lead to a normalization of relations with North Korea, a country that has frequently declared the United States an enemy that wants to take over.

"It's about attitude, it's about willingness to get things done," Trump said days before he's scheduled to talk with Kim about starting a process toward an agreement. "But I think I've been preparing for this summit for a long time, as has the other side."

“It’s going to be much more than a photo-op," Trump said before his White House meeting with another major player in Asia, Japanese Prime Minister Shinzo Abe.

Abe said he planned to speak with Trump about North Korea strategy, telling the president, "I would like to take this opportunity to make sure that we two have the utmost policy coordination as to our approach to the planned summit meeting."

During a news conference later, Trump and Abe pledged to work together on North Korea after the Singapore summit.

"Japan and the United States are always together," Abe said.

Trump said, "We could certainly like to see normalization" of relations with North Korea.

Trump said he might invite Kim to the White House, but only if things go well in Singapore.

If not, Trump said, he is prepared to end negotiations before they start in earnest, noting that he canceled the Singapore meeting before putting it back on the schedule.

"All I can say is I'm totally prepared to walk away," Trump said. "I did it once before."

Some Japanese are concerned that Trump will focus an agreement on the elimination of long-range missiles that threaten the United States while ignoring shorter-range weapons North Korea could use to threaten its neighbors, including Japan.

"The overriding concern is that Trump's eagerness to call the June 12th meeting a historical success will result in a bad deal," said Mireya Solis, a senior fellow and Japan specialist with the Brookings Institution.

Abe cited the fate of Japanese citizens kidnapped by the North Korean regime. Before their meeting in the Oval Office, the Japanese leader told Trump he seeks "progress on our efforts to address outstanding issues of concern, including the nuclear missile and the abductions issue."

Trump demands complete denuclearization before he considers easing sanctions on Kim's economy.

"They have to denuke," Trump said. "If they don’t denuclearize, that will not be acceptable. We cannot take sanctions off."