German chancellor Angela Merkel on Friday became the latest world leader to call for international action on the Amazon forest fires, backing concerns first voiced by France's president Emmanuel Macron.

Characterizing the fires as an "acute emergency" with a global impact, a spokesman for Merkel said the German leader believes the ongoing crisis belongs on the agenda of this weekend's Group of Seven summit.

"The extent of the fires in the Amazon area is shocking and threatening, not only for Brazil and the other affected countries, but also for the whole world.," the spokesperson told journalists in Berlin on Friday, according to Guardian.

Brazilian President Jair Bolsonaro has bristled at the growing international and domestic criticism of his administration's handling of the raging fires, which has blanketed some of Brazil's cities in acrid smoke that has blocked out the sun.

The Amazon rainforest is one of the world's best defenses against climate change and it's burning at an alarming rate.

Images of flames ravaging the rainforest have circulated broadly this week, provoking widespread concern over the world's climate change crisis and raising questions about what Brazil is doing to tackle the surge in fires.

In a deeply polarized country, reactions to the forest fires in the Amazon and to the international outcry has broken along familiar divisions. The left is planning protests throughout the country to condemn the environmental policies of the Bolsonaro administration critics say are exacerbating the unfolding crisis.

But the right, led by Bolsonaro, who campaigned last year the message of nationalism and anti-globalism, has criticized the outcry as modern day colonialism.

Flights throughout the Amazon were halted on Friday as heavy smoke obscured the visibility in the skies. Hospitals in the region reported an influx of patients suffering from smoke inhalation as rates of pneumonia and respiratory problems tripled in some states.

"Our house is burning. Literally, " French President Emmanuel Macron tweeted on Thursday.

But as Macron sounded the alarm, Brazil's president called him "sensationalistic," saying his suggestion betrayed a "misplaced colonialist mentality in the 21st century."

The powerful agricultural lobby that backed Bolsonaro's election grew increasingly nervous that international outrage would lead to a boycott of Brazilian goods abroad.

Earlier this week, two German newspapers called for sanctions against Brazil.

Brazil's speaker of the house Rodrigo Maia announced he will travel to Europe to convince France, Italy and Germany of Brazil's commitment to sustainability.

"We need to find a solution so that Brazil does not suffer sanctions in its agricultural sector," he said.

On Friday, Britain said prime minister Boris Johnson was "deeply concerned" and would use this weekend's summit to "call for a renewed focus on protecting nature and tackling climate change."

Some British politicians also joined the chorus of voices calling for a swift response to the fires.

"This isn't a freak accident: this is what a climate emergency looks like," Labour leader Jeremy Corbyn tweeted earlier this week.

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The Washington Post’s Terrence McCoy in Rio de Janeiro contributed to this report.