Representatives from the North and South Korea plan to meet Wednesday to discuss their upcoming and historic summit. South Korean President Moon Jae-in and North Korean leader Kim Jong Un will attend the first bilateral meeting between the two nations in more than a decade on April 27. The White House is also moving forward with plans for President Trump to meet Kim, but a time and place have not been announced.

The New Yorker's Evan Osnos, who traveled to North Korea last summer, said he thinks the Pyongyang's "heads are spinning as much as they are here in Washington and in New York." But he said he thinks "this is sincere."

"What's quite clear when you talk to people inside North Korea, when you talk to people outside, is that they recognize they were on an unsustainable path toward confrontation with the United States. So the question is how can you diffuse that and come up with a more sustainable arrangement," Osnos said Wednesday on "CBS This Morning."

Osnos said North Korea watches "every syllable" Mr. Trump says.

"We thought, well, maybe they've decided Donald Trump's their enemy. Actually, they haven't. They had allowed themselves the possibility that this man … might be the man who's going to sit down with us at the negotiating table. And they were waiting for the moment when the conditions were right. And when they were, they offered it," Osnos said.

During the possible negotiations, if Pyongyang is going to be asked to give up its nuclear program, what does the reclusive regime want in return?

"The biggest thing they want is some sort of reassurance of their own survival, meaning that they don't want to be on a path toward confrontation with the world's most formidable military. There's a lot of steps that they could look to, but that's the key thing," Osnos said.

North Korea will also be watching whether Mr. Trump recertifies the Obama-era Iran nuclear deal. Osnos said it "casts a shadow" over the possibility of reaching a deal with the North.

"North Korea is trying to decide, how much does Donald Trump stand by not only the words of his predecessors, but also the deals that he makes while in office? And if we pull out of Iran, that makes it harder," Osnos said.