Chris Christie meets with Zelenskyy during Ukraine trip

In an unannounced trip to Ukraine on Friday, former New Jersey Gov. Chris Christie -- now running for the Republican presidential nomination, met with President Volodymyr Zelenskyy in Kyiv.

The trip marks Christie's first visit to the ravaged nation since the start of the war in March 2022. The United States has positioned itself a diplomatic ally to Ukraine and sent billions of dollars' worth of assistance over its ongoing, nearly year-and-a-half-long war against Russia.

Christie met with Zelenskyy at the presidential palace in Kyiv. During the meeting, President Zelenskyy thanked Christie for visiting and for U.S. support in the war.

"It’s very important that all the country, all the Americans, are on the right side of the truth, democracy," Zelenskyy said.

Christie told Zelenskyy that the "biggest reason" he wanted to visit Ukraine was so he could see what was happening in Ukraine for himself.

"Because then it will best enable me to go home and describe to people in detail the things that I've seen," Christie said at the press event.

Christie noted that in his travels, he has seen many Americans show their support for Ukraine by displaying the blue and yellow Ukraine flag outside and around their homes.

"I believe that the overwhelming majority of the American people understand that we need to be with Ukraine on this fight," Christie told Zelenskyy. "But there are political arguments and I want us who support you to win those political arguments because that means the support will be better, faster and more significant."

Christie's itinerary included tours of various sites across multiple war-torn areas of the country, including a mass civilian burial site in Bucha and a history museum in the nation's capital, among other commemorative and educational sites.

He was also briefed on the March 2022 Ukrainian evacuation and the current states of the frontline, energy security, and U.S.-Ukrainian cooperation efforts.

While Christie has criticized the Biden, Trump, and Obama administrations for their handling of Russia, Christie has expressed ardent support of the United States' alliance with Ukraine.

"America has never been a great country and the leader of the world by filling in the moat and pulling up the drawbridge," he said on ABC's "This Week" in June.

Christie commented in a July town hall that he believes President Joe Biden has given Zelenskyy only the bare minimum supply of defensive aid. "And Joe Biden, by the way, is giving him just enough not to lose," Christie said, adding that he would give Ukraine "the F-16s, too."

In his "This Week" interview, Christie also emphasized his belief that the Ukrainians' fight with Russia is a "proxy war" against China, stating, "We need to make sure that we continue to engage in this way. We do not want a world that is dominated by Communist China. And so this is a fight that America needs to have. It always involves sacrifice. But in the end, at the end of this sacrifice, I am absolutely a believer in the fact that America will be bigger, stronger, richer and more influential in the world because we stood by our principles and stood by our friends."

Christie is not the only presidential contender to make the trip mid-campaign; Former Vice President Mike Pence, who announced his presidential bid in early June, made a surprise visit to Ukraine later that month. The two candidates are making their foreign policy stances on the war in Ukraine clear to potential voters before the 2024 election season revs up this fall with the first Republican debate scheduled for Aug. 23.

ABC News' Nicholas Kerr and Sarah Beth Hensley contributed to this report.