In a departure from prior statements, Sen. Ted Cruz announced Friday that he would vote for GOP presidential nominee Donald Trump.

“Our country is in crisis. Hillary Clinton is manifestly unfit to be president, and her policies would harm millions of Americans,” the Texas Republican wrote in a Facebook post. “And Donald Trump is the only thing standing in her way.”

Two months ago, Cruz shocked the Republican National Convention when he declined to throw his support behind Trump, and instead urged GOP voters to “vote your conscience.” Cruz’s fellow Republican lawmakers panned his convention speech as further dividing the party.

[The 5 Stages of Cruz and Trump]

Cruz cited a pledge he took as a former presidential candidate that he would support the eventual Republican nominee as one of the reasons for backing Trump. Cruz was a critical of Trump on the campaign trail, calling him a “pathological liar” and “amoral.”

But on Friday Cruz said that after months of reflection he decided to support Trump because Democratic nominee Hillary Clinton would be “wholly unacceptable” as president. Cruz said Trump’s list of potential Supreme Court justice nominees was one of the most important reasons for backing the GOP nominee.

In February, Cruz warned that Trump would likely strike a compromise with the next Senate Democratic Leader Charles E. Schumer, D-N.Y., on the next Supreme Court justice, leading to a less conservative court. But Trump’s release of his potential nominees apparently quelled that concern.

[Cruz Warns Trump and Schumer Would Cut SCOTUS Deal]

Trump unveiled Friday his final list for potential Supreme Court justices if he is elected president. Sen. Mike Lee, R-Utah, was on the list. Lee is one of Cruz’s closest allies in the Senate, and has refused to back Trump for president. Lee’s spokesman said Friday that the Utah senator does not have any plans to endorse Trump.

“For some time, I have been seeking greater specificity on this [Supreme Court] issue, and today the Trump campaign provided that, releasing a very strong list of potential Supreme Court nominees — including Sen. Mike Lee, who would make an extraordinary justice — and making an explicit commitment to nominate only from that list,” Cruz wrote Friday.

“This commitment matters, and it provides a serious reason for voters to choose to support Trump,” Cruz wrote.

Cruz also listed the Affordable Care Act, energy policy, immigration, national security and “Internet freedom” as key areas where Clinton and Trump disagree, which influenced his decision to back Trump.

Trump said in a statement that he was “greatly honored” by Cruz’s endorsement.

“We have fought the battle and he was a tough and brilliant opponent,” Trump said. “I look forward to working with him for many years to come in order to make America great again.” 

Trump and Cruz clashed on the campaign trail, where Trump nicknamed Cruz, “Lyin’ Ted.” Trump also went after Cruz’s wife, Heidi, retweeting a tweet with an unflattering picture of Heidi and threatening to “spill the beans” on her. Though it is not clear what Trump meant.

[Cruz Destructive, Ego-Mad, Furious Lawmakers Say]

The tension came to a head when Trump insinuated that Cruz’s father was connected to President John F. Kennedy’s assassination. Cruz had had enough, and lambasted Trump as a “pathological liar,” a “narcissist,” and “amoral.” That same day, Cruz lost the Indiana primary and suspended his presidential campaign.

[Cruz to GOP Delegates: ‘Vote Your Conscience’]

But the once tense relations between Cruz and Trump appeared to thaw this week when Trump backed a proposal the Texas Republican was championing in government funding negotiations. Cruz had been pushing lawmakers to block the U.S. Government from transitioning oversight of an Internet domain naming system to a global body.

Trump’s national policy director Stephen Miller said in a statement Wednesday that Trump supported blocking the transition. Cruz then took to social media to thank the nominee for his support.

Appreciate @realDonaldTrump’s support of our efforts to stop Obama’s Internet handover & keep the #Internet free https://t.co/rkHnu7kT4X

— Senator Ted Cruz (@SenTedCruz) September 21, 2016

Trump’s campaign manager, Kellyanne Conaway, also responded on Twitter, writing, “And we appreciate @tedcruz appreciating @realDonaldTrump. Over to you, @jeffroe.” Roe was Cruz’s presidential campaign manager. Before joining the Trump campaign, Conaway ran the Super PAC that was backing Cruz’s presidential bid.

Contact Bowman at bridgetbowman@rollcall.com and follow her on Twitter @bridgetbhc.