FORT WORTH, Texas -- Former presidential candidate and New Jersey Gov. Chris Christie endorsed Donald Trump for president today.

“I’m proud to be here to endorse Donald Trump,” Christie said at a campaign rally in Fort Worth, Texas, adding later, “I’m happy to be on the Trump team.”

Christie suspended his presidential campaign after finishing sixth in the New Hampshire primary, and announced he was supporting his former rival for a number of reasons.

“First is that Donald and I along with Melania and Mary Pat have been friends for over a decade. He has been a good and loyal friend to our family,” Christie said. “Secondly, I've been on that stage. I've gotten to know all the people on that stage. And there is no one who is better prepared to provide America with strong leadership that it needs both at home and around the world than Donald Trump.”

Christie said that Trump will “provide strong, unequivocal leadership” and would “undoubtedly” be the best candidate to beat “Hillary Clinton in November.

“They [Democrats] do not know the playbook with Donald Trump because he is rewriting the playbook. He is rewriting playbook of American politics because he is providing strong leadership that is not dependent upon the status quo," Christie said.

Trump introduced the New Jersey governor as a “friend for many years,” and did not dismiss the idea of having Christie as a potential running mate, “he’s got the talent.”

“He has been a spectacular governor. He has been just a wonderful person and a wonderful loyal person. Done a really good job, totally destroyed Marco Rubio the other day,” Trump said, referring to the time during the Feb. 6 Republican debate that Christie pointed out that Rubio repeated himself four times.

Christie had Trump’s back today, calling Rubio's comments earlier today about Trump "desperate."

“The fact is desperate people do desperate things. And I've seen it throughout politics and so have you," Christie said. "And so the idea that Marco Rubio can get inside of Donald Trump's head is interesting proposition but one that is really for the D.C. parlor games.”

The New Jersey governor said he made his decision Thursday morning. Coming the morning after Marco Rubio had a measure of success taking Trump on on the debate stage, the timing of Christie’s endorsement couldn’t have been better for Trump. No one has attacked Rubio as effectively as Christie has.

At Trump’s campaign rally following the news conference, Christie called the Florida senator out, saying: “Being President of United States is not a no-show job like you treated the U.S. Senate.”

While Christie was still in the race for the White House, when asked to explain the appeal of Trump, he mocked the GOP front-runner, but added he was a “generous guy.”

During his formal announcement, Christie said he wanted to beat Trump, but "that part is over" and Trump is the "best person" for the job.

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