In an emotional interview on CNN, Rodman said Trump reached out to him about his past efforts to relay messages from Kim.
Dennis Rodman was seen in Singapore sporting a MAGA hat, a red baseball cap with President Trump's election campaign slogan "Make America Great Again". "We just need the doors to be opened so we can start fresh", he said.
"It's unbelievable, it's awesome, it's incredible".
Emblazoned in peace-themed PotCoin.com apparel - the freakish corporate sponsor of Rodman's visit for the impending North Korea-US talks - the five-times National Basketball Association champion touched down in Singapore round midnight on Monday, telling reporters he was here "to see what's going on", and hoping "that things turn out to be well for everyone in the world". But I kept my head up high. I was the only one who felt so. No one to see me.
"I took those bullets, I took all that, I took everything that everyone came at me and I'm still standing".
"Today is a great day for everybody, Singapore, Tokyo, China. And I think that people see now that I do care what's really going on and that's why I'm over here".
Discussing his relationship with Kim, Rodman said the North Korea dictator was "more like a big kid" who "loves to have a good time". He wants to come to America. "He wants his people to enjoy his life".
He described how he carried an offer of talks from Kim to Barack Obama after his first meeting.
"I gave him something for his birthday ..."
Rodman also goes back years with Mr Trump and appeared on his Celebrity Apprentice show. "He said: Can you do that". Even though I couldn't do it, I knew if I fail now there is going to be a problem. I was sitting up protecting everything.
CNN's Chris Cuomo noted about Rodman on Monday night, "He is our best resource at this point right now for understanding the minds of the two men, especially Kim Jong Un". "Dennis Rodman was either drunk or on drugs (delusional) when he said I wanted to go to North Korea with him". He told reporters he wasn't sure if he would meet Kim in Singapore. "He's trying to progress his country".
The White House has since said that he will play no role in the discussions.
Moments after President Trump and the North Korean leader signed documents outlining their framework for future peace talks, the basketball great - who traveled to Singapore for the historic summit - called Kim "a great guy".