White House press secretary Sarah Huckabee Sanders said that planning continues for the historic summit in Singapore and that negotiators from the United States and North Korea are meeting at the Demilitarized Zone to lay the groundwork.
With the North-U.S. summit one week away, Kim's activities are being closely monitored.
Easing sanctions under a deal would likely need approval from Congress which has passed sanctions on North Korea.
North Korea could use its minerals as collateral to get funding to develop its economy, according to Lee Yoon-sok, a researcher at the Korea Institute of Finance in Seoul.
He stressed that the Singapore meeting is part of a "process" that will go on for some time: "I told them today, 'Take your time". Economically at least, there could be plenty of upside.
Sanders also deflected a question about whether Trump supports Russian President Vladimir Putin's reported invitation to meet with Kim.
The moves are likely meant to surround Kim with a younger, even more trusted cohort of officials whom he can rely on as he confronts a slew of domestic and global issues, said Michael Madden, a North Korea expert at Johns Hopkins University's 38 North website.
Sen. Marco Rubio, R-Fla., greets officers as he arrives for a meeting between US President Donald Trump and law enforcement officers at Broward County Sheriff's Office in Pompano Beach, Florida, February 16, 2018.
The International Campaign to Abolish Nuclear Weapons has also offered to chip in a share of the million dollars it was awarded for winning the Nobel Peace Prize past year.
But efforts may have been frustrated, owing to North Korea's lack of cooperation with initial US weapon demands, a South Korean foreign ministry official told the paper.
The decision to move ahead with the summit came after a week of frenzied diplomacy topped off with a top North Korean official visiting the White House to deliver Trump a letter from Kim.
"To be honest, I was surprised that Trump clearly stated that he had not talked about human rights", a source close to Japan-U.S. diplomacy said on Saturday".
Kim is unlikely to spend much time in Singapore.
"We feel like things are continuing to move forward, and good progress has been made".
Foreign Minister Sergei Lavrov proposed the location and time during a meeting recently in Pyongyang with Kim, Kremlin spokesman Dmitry Peskov, said on Monday in Moscow.