Trump and first lady Melania Trump arrived in Paris earlier in the day and met with Macron at the Elysee Palace.
"This is a world national celebration and we look very much forward to it," Trump said at a joint news conference. "France is America's first and oldest ally."
Trump noted the date Thursday -- Bastille Day in France and the 100th anniversary of the United States entering World War I -- which came one day before the one-year anniversary of the terrorist attack in Nice.
"We all remember that, how horrible that was," Trump said, emphasizing his agenda to fight terrorists, whom he called "enemies of humanity."
Trump also cited support from Macron in further counter-terrorism efforts.
"I applaud President Macron for his courageous call for less bureaucracy and a Europe that protects its citizens," the president added, noting that, "we did not become great through regulation."
In his remarks, Trump also pledged to work with France on environmental efforts.
"We live in a very complex world. We have to respect it. The United States remains committed to being a leader in environmental protection while we advance energy security and economic growth."
"We know what our disagreements are," Macron said. "I think its important we can continue to talk about it. I very much respect the decision taken by President Trump [to abandon the Paris agreement]."
Macron repeatedly mentioned a "roadmap" for attaining common goals between both countries.
"We underlined a number of shared convictions and, most important, the joint roadmap in order to work together," he said. "When it comes to fighting terrorism, from day one, I can say we've seen eye-to-eye.
"We have a shared determination."