Bill Glauber and Daniel Bice

The Milwaukee Journal Sentinel

After a month of meetings and phone conversations, House Speaker Paul Ryan went to his hometown newspaper to declare what many saw was inevitable.

Ryan endorsed presumptive Republican nominee Donald Trump on Thursday, saying he would vote for the New York mogul in the fall.

"It's no secret that he and I have our differences," Ryan wrote in an opinion piece submitted to the Janesville Gazette. "I won't pretend otherwise. And when I feel the need to, I'll continue to speak my mind. But the reality is, on the issues that make up our agenda, we have more common ground than disagreement."

Those close to Ryan said the Janesville Republican and 2012 GOP vice presidential nominee reached the decision earlier this week. He spoke most recently to Trump sometime last week.

Trump's courting of Ryan has gone on for weeks as he sought to unite the Republican Party.

Paul Ryan says he's not ready to back Trump

Trump, Ryan pledge to work together — but no endorsement

In style and substance, Ryan and Trump are polar opposites.

Ryan has emerged as an intellectual force in conservative circles, while Trump brashly stormed through the Republican primaries, collecting enough delegates to secure the party's nomination.

In doing so, Trump appeared at odds with party principles on entitlements and national security. He also made immigration a central focus of the race, while Ryan had spent years trying to secure a compromise on the complex issue.

Ryan campaign spokesman Zack Roday said the column is an endorsement of Trump.

Following Ryan's announcement, Trump tweeted that it was "great to have the endorsement and support of Paul Ryan. We will both be working very hard to Make America Great Again!"

In his role as House speaker, Ryan has emerged as a key bridge between the party's establishment and more conservative wing. He also wields enormous power, helping shape his party's agenda.

In early May, Ryan told CNN he wasn't "ready" to back Trump. Four days later, he told the Journal Sentinel said he was willing to step down as chairman of the GOP convention if Trump asked.

In his opinion piece, Ryan wrote of the importance of House Republicans putting together an agenda to unite the party as well as the country. House Republicans will be rolling out that agenda beginning next week.

"One person who we know won't support it is Hillary Clinton," Ryan said of the likely Democratic presidential nominee.

Ryan wrote: "Donald Trump and I have talked at great length about things such as the proper role of the executive and fundamental principles such as the protection of life. The list of potential Supreme Court nominees he released after our first meeting was very encouraging."

Ryan said the main focus of the talks revolved around the House policy agenda in such areas as health care, national security and the economy.

"We've talked about the common ground this agenda can represent," Ryan said in his Janesville column. "We've discussed how the House can be a driver of policy ideas. We've talked about how important these reforms are to saving our country. And we've talked about how, by focusing on issues that unite Republicans, we can work together to heal the fissures developed through the primary.

"Through these conversations, I feel confident he would help us turn the ideas in this agenda into laws to help improve people's lives. That's why I'll be voting for him this fall."

In an interview with the Associated Press, Ryan said Trump didn't offer any deals in exchange for the endorsement. Ryan said the two still have their differences but he wanted to reach the right "comfort level" before endorsing Trump.

"It is my hope the campaign improves its tone as we go forward and it's all a campaign that we can be proud of," Ryan said.

Democratic National Committee Chairwoman Debbie Wasserman Schultz blasted Ryan's move.

"When he initially refused to endorse Trump four weeks ago, Paul Ryan said it was time to set aside bullying and belittlement," she said in a statement.

"But with his tepid, halfhearted endorsement (Thursday), Ryan has backed away from his own criticisms of Trump's dangerous, divisive campaign, bowed down, kissed the ring, and conceded that Trump is the leader of the Republican Party."

Elections 2016 | USA TODAY Network