French President Emmanuel Macron on Monday condemned "extraordinarily rude" comments made about his wife Brigitte by Brazilian President Jair Bolsonaro.

"He has made some extraordinarily rude comments about my wife," Macron told a press conference when asked to react to statements about him by the Brazilian government.

"What can I say? It's sad. It's sad for him firstly, and for Brazilians," he added.

On Sunday, Bolsonaro endorsed a sexist Facebook post about France's first lady Brigitte Macron.

A Bolsonaro supporter had posted a meme mocking the appearance of Brigitte Macron and comparing her unfavourably with Brazil's first lady Michelle Bolsonaro, with the tagline: "Now you understand why Macron is persecuting Bolsonaro?"

The far-right Brazilian leader replied: "Do not humiliate the guy, ha ha," referring to Macron.

Asked by AFP whether the response came from Bolsonaro himself, a spokesman for Brazil's presidential palace refused to comment.

Brazilian President Jair Bolsonaro and his wife.

President Macron last week called for emergency talks by G7 nations on the fires destroying chunks of the Amazon rainforest, piling pressure on Bolsonaro, who in turn accused him of having a "colonialist mentality"

The fires across the world's largest rainforest, which experts have blamed on rampant deforestation, have triggered a global outcry -- with European nations leading the charge against Bolsonaro, who has made no secret of his skepticism about climate change.

The row has seen Brazilian politicians -- including Bolsonaro's son Eduardo -- take potshots at Macron, with education minister Abraham Weintraub calling him "an opportunist idiot" and "a president without character" in a flurry of tweets Sunday.

Eduardo Bolsonaro, who is tipped to be the next ambassador to Washington, on Friday retweeted a video showing violent yellow-vest protests in France headlined "Macron is an idiot", calling it "a message" to the French leader.

Macron has accused Bolsonaro of lying about a June pledge to fight global warming and threatened to block efforts to seal a major trade deal between the EU and South America's Mercosur nations over the Amazon crisis.

Ties between Brazil and France have plunged since Bolsonaro's election. Last month the Brazilian leader snubbed France's top diplomat by cancelling their meeting and getting a haircut instead, which he broadcast live on Facebook.

Jean-Yves Le Drian had angered Bolsonaro by meeting with non-profit organisations which have been critical of the South American leader.

Last week Bolsonaro accused non-profit organizations of deliberately starting the fires after their funding was cut.