Kim also said he would wait until the end of the year "for the U.S. to make a courageous decision" on another meeting, after his most recent summit with Trump in Vietnam broke down and both sides left without agreement.
Washington has blamed the February deadlock on the North's demands for sanctions relief in return for limited nuclear disarmament, but Pyongyang said it had wanted only some of the measures eased.
In a speech to Pyongyang's parliament Friday, Kim said the Hanoi meeting had made him question whether Washington is "genuinely interested" in improving its relations with Pyongyang.
"We are willing to give another try if the U.S. offers to have a third summit with the right attitude and mutually acceptable terms," he said, according to a report by North Korean state media outlet KCNA.
Kim added that his personal relationship with Trump remained strong, adding they could "write letters to each other" whenever they wanted.
"We will wait with patience until the end of the year for the U.S. to make a courageous decision," Kim said.
Trump and Kim held their first landmark summit in Singapore last June, where the pair signed a vaguely-worded agreement on the "denuclearization of the Korean peninsula."
But the failure to reach agreement at their second summit in Hanoi has raised questions over the future of the accord.
Trump said Thursday he was mulling a third summit with Kim ahead of a meeting with his South Korean counterpart Moon Jae-in at the Oval Office -- a move supported by Seoul.
"Our government will do what we can in order to maintain the current momentum for dialogue," Moon's office said in a Saturday statement.
On Friday, the KCNA reported Kim was re-elected as chairman of the State Affairs Commission, the North's most important decision-making body.