Trump, however, stressed during a 15-minute meeting with special envoy Hong Seok-hyun that he won't hold talks with the North for the sake of talks, the envoy said. Also in attendance at the meeting were Vice President Mike Pence, National Security Advisor H.R. McMaster and Trump's son-in-law and senior adviser, Jared Kushner, according to the Yonhap.
It was the first time Trump has met with a South Korean official since taking office.
The meeting came just days after North Korea successfully test-fired a new intermediate-range ballistic missile Sunday demonstrating the big strides that the regime has made in its pursuit of developing an intercontinental ballistic missile capable of delivering a nuclear weapon to the U.S.
"(President Trump) talked about sanctions on North Korea and cooperative relations with China. And he said he looks forward to cooperating closely with President Moon in resolving the North Korean nuclear issue so as to produce an outcome," Hong said.
"Though we're now at the stage of pressure and sanctions, he said he has a willingness to make peace through the so-called engagement if certain conditions are right. He said, however, that what he's willing to do is not talk for talk's sake but for talks that produce an outcome," the envoy said.
Hong said he handed Moon's letter to Trump and expressed thanks for supporting South Korea's security and inviting Moon to visit Washington. Trump was quoted as saying that he very much looks forward to next month's summit. The two countries agreed earlier this week to hold a summit between Moon and Trump in Washington in late June.
"President Trump talked mainly about big pictures, and emphasized that we can achieve an outcome through the strong unity of the alliance and international cooperation," Hong said.
Hong also said he held a separate meeting with McMaster and talked briefly about the THAAD deployment.
"I said there is a controversy about procedural problems in the course of the deployment, and I talked about the need for this issue to be discussed at the National Assembly," Hong said.
In response, McMaster said the U.S. is aware of and understands various talks about such procedural problems, Hong said, adding that the meeting was mostly about the North Korean nuclear issue. The issue of THAAD's cost didn't come up during the meeting, he said.
During the campaign, Moon was critical of the decision to host THAAD, saying that the decision was made without due process to collect public opinion. Presidential aides say the stance does not necessarily mean Moon is opposed to the deployment.
Trump fueled opposition to THAAD among the South Korean public by demanding the South pay for the US$1 billion system. The demand runs counter to a deployment agreement in which the U.S. agreed to pay for the system if the South agreed to host it and provide land.
Hong arrived in Washington earlier in the day for a four-day visit. He is expected to hold meetings with other senior U.S. government officials and experts at major think tanks.