French President Emmanuel Macron has made a strong pledge to stand by the accord and similar reactions from India and China.
"America is perceived as being, on this, on the wrong side of history," Ambassador Francois Delattre told reporters.
Trump announced the US exit from the 190-plus nation pact last week, drawing strong criticism from allies in Europe who vowed to turn to China and other countries as partners to implement the 2015 deal.
French President Emmanuel Macron has made a strong pledge to stand by the accord and similar reactions from India and China confirm that the Paris deal is "our common roadmap" to a low-carbon world, Delattre said.
The United States, the world's biggest carbon emitter after China, signed the agreement last year under the previous administration, but Trump has argued that the deal would harm the US economy.
Delattre said Trump's decision "goes beyond climate change policy" and is a "factor in the erosion of the moral and political leadership of the United States."
The decision could be perceived as "the birth certificate of the multipolar world" in which the United States is no longer "the most reliable guarantor of the world order," he added.
Trump's decision to scrap the Paris deal has left him isolated on the world stage and prompted a backlash at home, with several state governors, city mayors and powerful companies already drawing up plans to meet the pact's emission targets -- without Washington's backing.
Despite the setback on climate, Delattre expressed hope that the United States will nevertheless remain engaged in global affairs.
"A lasting American withdrawal from world affairs could give rise to a return to old spheres of influence whose dire consequences we are already familiar with," he said.