Signalling newfound bonhomie, presumptive Republican presidential nominee Donald Trump and the powerful House of Representatives Speaker Paul Ryan on Thursday met face to face for the first time and vowed to unite the party to ensure victory in the November polls.
"The United States cannot afford another four years of the Obama White House, which is what Hillary Clinton represents," Trump and Ryan said in a joint statement after their meeting at the Republican National Committee headquarters near the US Capitol.
The two leaders said they are "totally committed to working together" and called for "shared principles" and a "conservative agenda".
The much anticipated meeting comes a week after Ryan said he is not ready yet to support Trump as the party's presidential nominee.
But, in a softening of stance, Ryan on Tuesday had indicated that he may back Trump after getting to know him better.
Trump, 69, emerged as the party's presumptive presidential nominee after winning the Indiana primary in which he defeated Texas Senator Ted Cruz.
Cruz and the other Republican candidate Ohio Governor John Kasich dropped out of the race soon after.
"It is critical that Republicans unite around our shared principles, advance a conservative agenda, and do all we can to win this fall," Trump and Ryan said in their statement, according to which the two leaders had a "great conversation".
However, they also acknowledged that their were differences between them.
"While we are honest about our differences, we recognise that there are also many important areas of common ground," the statement said.
"We will be having additional discussions, but remain confident there is a great opportunity to unify our party and win this fall, and we are totally committed to working together to achieve that goal," it said.
"This was our first meeting, but it was a very positive step toward unification," said the statement, which fell short of a formal endorsement of Trump by Ryan.
Ryan said he would work with Trump to prevent Clinton of the Democratic party from entering the White House by winning the November general elections.
"We want to beat Hillary Clinton," Ryan told a crowded news conference at the Capitol Hill soon after his meeting with Trump.
"We had a very encouraging meeting. Look, it's no secret that Donald Trump and I have had our differences. We talked about those differences today. That's common knowledge. The question is: What is it that we need to do to unify the Republican Party and all strains of conservative wings in the party? We had a very good and encouraging, productive conversation on just how to do that," Ryan said.
"It was important that we discussed our differences that we have. But it's also important that we discussed the core principles that tie us all together; principles like the Constitution, the separation of powers, the fact that we have an executive that has gone way beyond the boundaries of the Constitution and how it's important to us that we restore Article I of the Constitution," Ryan said.
"It's the principle of self-government. We talked about life and how strongly we feel about this core principle. We talked about the Supreme Court and things like this. I was very encouraged with what I heard from Donald Trump today," he said.
"I do believe that we are now planting the seeds to get ourselves unified, to bridge the gaps and differences. And so from here, we are going to go deeper into the policy areas to see where that common ground and how we can make sure that we are operating off the same core principles," Ryan added.
The two leaders met for 45 minutes to discuss a series of issues and draw a road map to sort out their differences.
"I was very encouraged with this meeting, but this is a process. It takes a little time,” he said in response to a question.
However, Ryan did not give a 'Yes' or 'No' answer if he has endorsed Trump.
"I think this is going in a positive direction. And I think this was a first, very encouraging meeting," he said.
"It is important that the kind of conversation we had is between the two of us. And no offense, I don't want to litigate our conversation through the media, because I think when you're beginning to get to know someone, you have a good conversation of trust between each other," Ryan said.
"So, I want to keep the things we discussed between the two of us, because they were very important and they were personal in some senses. And that means we talked about what it takes to unify, where our differences were and how we can bridge these gaps going forward, so that we are strong as a party going into the fall," Ryan said.