President Trump meets with South Korean President Moon Jae-In in the Oval Office Tuesday.

Evan Vucci, AP

WASHINGTON — President Trump suggested Tuesday that the June 12 date for his historic summit with North Korea's leader could slide back on the calendar, saying, "If it doesn't happen, maybe it will happen later.

“You never know about deals," he said as he met with his South Korean counterpart in the Oval Office. "I’ve made a lot of deals. You never really know.”

Trump and South Korean President Moon Jae-in met for a high-stakes strategy session at the White House Tuesday as the two leaders prepare for what would be a historic summit with North Korea next month in Singapore.

But even as the United States and South Korea insisted that they haven't given up on peace talks, there were hints that the overture may be built on slippery foundations.

"We believe there is a 99.9% chance the North Korea-U.S. summit will be held as scheduled," South Korea's national security adviser, Chung Eui-yong, told reporters on his way to Washington. "But we're just preparing for many different possibilities."

No sooner was a day and place set for the summit — June 12 in Singapore — than the assumptions underpinning the meeting began to erode. Trump had agreed to meet with North Korean leader Kim Jong Un based on South Korea's representations that North Korea would agree to the talks without preconditions.

But in recent weeks, North Korea has ramped up its rhetoric, insisting that the United States and South Korea end joint military exercises and suggesting it doesn't want to give up its nuclear weapons after all.

"We're trying to understand the situation from the North's perspective," Chung said, according to the Yonhap news agency.

Chung said the Trump-Moon talks would be "candid discussions on how to make the North-U.S. summit a success and produce significant agreements and how to best implement those agreements."

A man waits to cross a street in Rason. at the northeastern tip of North Korea, Nov. 21, 2017.

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A man waits to cross a street in Rason. at the northeastern tip of North Korea, Nov. 21, 2017.

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For its part, the Trump administration continued to signal that the summit won't produce easy results.

“I don’t think President Trump is thinking about public relations, he’s thinking about peace," Vice President Pence told Fox News Monday. "I mean truthfully the Clinton administration, even the Bush Administration, got played in the past."

Trump suggests North Korea summit could be delayed while he huddles with South Korea

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