US House Speaker Paul Ryan is refusing to support Donald Trump as the Republican presidential nominee. Trump became the Republican party's presumptive presidential candidate after marking victory in the Indiana primary.

He said that, "I'm just not ready to do that at this point. I'm not there right now." "And I hope to. And I want to, but I think what is required is that we unify this party."

"I am not ready to support Speaker Ryan's agenda. Perhaps in the future we can work together and come to an agreement about what is best for the American people," Trump said. "They have been treated so badly for so long that it is about time for politicians to put them first!"

"I think what a lot of Republicans want to see is that we have a standard bearer that bears our standards,"  Ryan said.

Paul Ryan is the single most effective tool and person to maintain control of the Senate and the House," said Zwick. "He's focused on an agenda. He's constantly out there talking about his agenda."

Also read: Ted Cruz ends campaign, Trump on his way to Republican nomination

- Nandini