WASHINGTON, March 8 (Xinhua) -- U.S. President Donald Trump has agreed to meet Kim Jong Un, top leader of the Democratic People's Republic of Korea (DPRK), by May at the invitation of Kim "to achieve permanent denuclearization", a visiting South Korean envoy said here on Thursday.

Trump could be the first sitting U.S. president to meet the DPRK's top leader, which observers say would be a big step forward to resolving the Korean Peninsula nuclear issue.

Kim has said the DPRK "will refrain from any further nuclear or missile test," Chung Eui-yong, South Korea's top national security adviser, told reporters at the White House after briefing Trump on the outcome of a South Korean delegation's meeting with Kim earlier this week.

Kim was also committed to denuclearization of the DPRK, Chung added.

"He (Kim) understands that the routine joint military exercises between the Republic of Korea and the United States must continue," said Chung, who arrived in Washington Thursday with South Korean National Intelligence Service Director Suh Hoon.

The White House has announced that routine U.S. military exercises with allies in Asia will continue. The next U.S.-South Korean drill is expected in April.

Signs of further detente on the Korean Peninsula were detected as Kim made a tension-easing gesture during the the high-level South Korean delegation's two-day visit to Pyongyang. For the first time since he assumed power, Kim personally hosted a dinner for the delegation.

"He expressed his eagerness to meet President Trump as soon as possible," Chung said in Washington.

"Trump appreciated the briefing and said he would meet Kim Jong Un by May to achieve permanent denuclearization," the South Korean envoy added.

White House Press Secretary Sarah Sanders said Trump "will accept the invitation to meet with Kim Jong Un at a place and time to be determined."

"We look forward to the denuclearization of North Korea (DPRK). In the meantime, all sanctions and maximum pressure must remain," Sanders added.

Washington has been pushing forward its "maximum pressure" campaign against Pyongyang mainly through economic sanctions and diplomatic isolation. Experts say the strategy may not achieve its expected results but could further escalate tensions.

During the visit of the South Korean delegation, the DPRK showed willingness to talk "candidly" with the United States on issues including denuclearization of the Korean Peninsula and normalization of ties with Washington. It also agreed to hold the third inter-Korean summit in late April.

On Thursday, Chinese Foreign Minister Wang Yi urged the United States and the DPRK to hold talks sooner rather than later. He also called for resolving the legitimate security concerns of all sides including the DPRK on an equal footing.