LONDON — European leaders have reacted with growing fear and anger to the fires ravaging Brazil’s rain forest, calling it a worldwide crisis that is accelerating global warming — and one that Brazil’s leader appears unwilling to combat.

President Emmanuel Macron of France went so far, on Friday, as to accuse President Jair Bolsonaro of Brazil of lying about being committed to fighting climate change and protecting the Amazon forest.

As a result, Mr. Macron said, he would try to kill a major trade deal between Europe and South America that has been years in the making.

Mr. Macron’s statement was an escalation in a series of sharp comments and accusations he has traded with Mr. Bolsonaro, an unusually harsh exchange between the leaders of two democracies.