Republican presidential candidate Donald Trump will hold an usual tete-a-tete on Thursday with Paul Ryan, the country's top elected Republican, to see if they can begin healing fissures in the party created by Trump's insurgent candidacy.

Party leaders are normally eager to rally around a presidential nominee in order to unite forces for the general election battle. But Ryan, the U.S. House of Representatives speaker, has withheld his endorsement of Trump out of concern over his incendiary tone and policy ideas that run counter to deeply held Republican doctrine.

Both Trump, the presumptive nominee, and Ryan struck a conciliatory tone before their 9 a.m. EDT meeting at the headquarters of the Republican National Committee, a session that will include RNC Chairman Reince Priebus, a Ryan friend who wants unity for the party.

"I have a lot of respect for Paul Ryan," Trump said on Wednesday on Fox News Channel's "Fox and Friends. "We'll see what happens. If we make a deal, that will be great. And if we don't, we will trudge forward like I've been doing and winning, you know, all the time."

Trump last week became the presumptive nominee for the Nov. 8 election after his remaining rivals, U.S. Senator Ted Cruz of Texas, and Ohio Governor John Kasich, dropped out. His likely general election rival is Democratic front-runner Hillary Clinton.

Ryan told reporters on Wednesday he just wanted to get to know Trump.

"There is plenty of room for different policy disputes in this party. We come from different wings of the party. The goal here is to unify the various wings of the party around common principles so we can go forward unified," Ryan said.

Ryan was the running mate with 2012 Republican presidential nominee, Mitt Romney, a harsh Trump critic.

The meeting was not expected to lead to an immediate endorsement by Ryan, who opposes Trump's proposals to temporarily ban Muslims from entering the United States, deport 11 million illegal immigrants and impose protectionist trade policies. Trump has also sent mixed signals on whether he would raise taxes if elected.

The billionaire New York businessman and former reality television star has shown little inclination to change tactics and policy positions that have carried him to the cusp of the presidential nomination.

Trump will also meet with Senate Republican leaders, including Majority Leader Mitch McConnell, and other House Republican leaders. A chief concern among congressional Republicans is whether Trump will be a strong enough candidate in the November election to ensure the party maintains control of Congress.

HIGH BAR

U.S. Representative Charlie Dent of Pennsylvania, a Republican moderate, told reporters that Ryan had struck the right tone so far in reflecting the sentiment of those Republicans who carry lingering concerns about Trump.

"A number of us are concerned about the lack of policy positions that he (Trump) has presented. The few that he has are often conflicting or contradictory. Combine that with the incendiary statements on POWs, the disabled, Muslims, Hispanics, women, it's a cause for concern," Dent said.

U.S. Representative Steve King, an Iowa Republican who backed Cruz in the primary race, said Trump needed to acknowledge the conservative bent of the Republican Party. "I'm saying again to Donald Trump: Reach out to the conservatives, start that process, recognize you're not going to be elected president without it," King said on MSNBC.

Republican strategist Doug Heye said Trump has a high bar to convince skeptical party loyalists about his candidacy.

"It's not so much about trade or what his tax plan will be," Heye said. "It's the broader messaging that for the past eight months has told women and minority communities throughout the country that the Republican front-runner doesn't want them, doesn't need them and doesn't care about them."

U.S. Representative John Fleming of Louisiana, a Republican favorite of the conservative Tea Party movement who supports Trump, said the Ryan-Trump meeting would begin the process of unifying the party, which may last until the July 18-21 nominating convention in Cleveland.

"I really think everything has to be resolved by the end of the convention," he said.