Mike Pence breaks with Donald Trump, endorses Paul Ryan

Indiana Gov. Mike Pence on Wednesday endorsed House Speaker Paul Ryan, a significant break with his running mate, Donald Trump, who tossed acid on an already-tepid relationship with the Wisconsin Republican by declining to support his reelection bid the day before.

Pence told Fox News in a phone interview that he was "strongly encouraged" by Trump to support his longtime friend in Tuesday's primary.

"He strongly encouraged me to endorse Paul Ryan in next week's primary, and I'm happy to do it," Pence said.

The endorsement came just one day after Trump shocked the political world by refusing to back Ryan, the highest-ranking elected Republican in the country.

"I like Paul, but these are horrible times for our country," Trump said in an interview with The Washington Post. "We need very strong leadership. We need very, very strong leadership. And I'm just not quite there yet. I'm not quite there yet."

Ryan's long-shot primary rival Paul Nehlen has fully embraced Trump's ideology, railing against the finance industry and the speaker's support for some international trade agreements.

In an interview with Business Insider on Tuesday, Nehlen said that Trump was "fed-up" with Ryan over the distant relationship between the two Republican party leaders.

"Why does he weigh in on issues that, on the negative side, every time with Mr. Trump?" Nehlen asked of Ryan. "[Trump's] our nominee. He takes every opportunity to take a shot at Mr. Trump."