Trump appeared on NBC's Meet The Press Sunday and told host Chuck Todd that he was "blindsided" by Ryan's refusal to endorse him for the presidency.
"I have a nice relationship with him. Don't know him well. Met him one time," Trump said. "But have a nice relationship with him. And then all of a sudden, he gets on and he does this number. So I'm not exactly sure what he has in mind. But that's okay."
The feud between Trump and the current speaker of the house began when Ryan told CNN that he wasn't ready to support Trump. Trump swiftly shot back with statement saying he wasn't wasn't "ready to support Speaker Ryan's agenda."
The conversation shifted to whether or not Trump would boot Ryan from his current position.
"If he can't endorse you, do you think he should be chair of the Convention?" Todd asked Trump.
Trump said if he was faced with that decision he would be "very quick with the answer." Trump also told Todd that he didn't think Ryan's stance would hurt him. "And I'd like to have his support, but if he doesn't want to support me that's fine," he insisted.
Meanwhile, as Trump slammed Ryan on NBC, 2008 vice presidential hopeful Sarah Palin told CNN that Ryan would soon be "Cantored," referring to Eric Cantor, the first sitting House majority leader to lose a primary race.
Palin, who endorsed Trump in January, said she believed Ryan was now hurting his political aspirations in his refusal to support Trump.
"His political career is over, but for a miracle, because he has so disrespected the will of the people," Palin said.
"For him to already come out and say who he will not support was not a wise decision..." Palin added. The former Alaskan governor then said she felt Ryan was not endorsing Trump because he didn't want to "screw his chances for the 2020 presidential bid." She said she believes that Ryan doesn't want the GOP to win now, so that he will have a better chance of winning later.
While on NBC, Trump also directed his vitriol at 2012 GOP nominee, Mitt Romney, Ryan's former running mate.
Romney called out Trump in March, saying Trump "lacked the temperament to be president" and that he was nothing more than a demagogue.
The billionaire shot back Sunday, saying Romney was "ungrateful" for the support he offered him in the 2012 Republican primary. "Every single robocall I made, he won that state. Every single speech I made, he won that state, in terms of the primaries," Trump said.
When asked if he thought Romney was ungrateful, Trump said, "He was ungrateful. Which is okay. A lot of people are ungrateful. But he was ungrateful. They did not respond accordingly."