Scott Walker unloads on Donald Trump while exiting the race

Wisconsin Gov. Scott Walker (R) suddenly started bashing Republican front-runner Donald Trump on Monday while exiting the 2016 presidential race.

Walker had declined to take direct shots at Trump even as the real-estate mogul tore into him on the campaign trail for not shutting down one of his supporters who called Trump a "DumbDumb."

But on Monday, Walker made it abundantly clear that he was no fan of caustic tone being offered by "the current front-runner."

"Today, I believe that I am being called to lead by helping to clear the field in this race so a positive, conservative message can rise to the top of the field. With this in mind, I will suspend my campaign immediately," he said.

Walker added: "I encourage other Republican presidential candidates to do the same so that voters can focus on the limited number of candidates who can offer a positive, conservative alternative to the current front-runner." 

He also took a couple other shots at Trump during his remarks, including references to Trump's "Make America Great Again" slogan, his shoot-from-the-hips trash-talk, and his frequent complaints about the current state of the country.

"Sadly, the debate taking place in the Republican Party today is not focused on that optimistic view of America," Walker said after touting the record of former President Ronald Reagan.

"Instead, it has drifted into personal attacks. In the end I believe that the voters want to be for something and not against someone," he continued. "Instead of talking about how bad things are, we want to hear how we can make them better for everyone."

For his part, Trump praised Walker as a "very nice person" after the news broke that he was dropping out:

Trump's response was very similar to how he addressed former Texas Gov. Rick Perry's (R) withdrawal from the White House race.

Perry, who feuded with Trump far more prominently, also torched Trump on his way out. But Trump responded by complimenting him: