WASHINGTON - US President Donald Trump said on Tuesday that his upcoming meeting with the Democratic People's Republic of Korea (DPRK) top leader Kim Jong-un was being set up and about "three or four" locations were being considered.

In the Oval Office, Trump revealed the latest development about his second meeting with Kim while announcing the resignation of Nikki Haley as US ambassador to the United Nations.

"We are talking about three or four different locations, timing won't be too far away," the US president said.

He noted that there was only a dim possibility of greeting the DPRK top leader in Singapore again, where the first Trump-Kim meeting took place in June. "We will probably do a different location," he said.

US Secretary of State Mike Pompeo paid a trip to Pyongyang over the weekend and met with Kim for over three hours, discussing issues concerning the denuclearization on the Korean Peninsula as well as the details of the second summit between the two leaders.

The discussions were described as "productive" by both sides.

The first-ever DPRK-US summit was held in Singapore on June 12. Under a joint statement signed by Trump and Kim, the United States would provide a security guarantee to the DPRK in return for Pyongyang's commitment to denuclearizing the Korean Peninsula.