Hundreds of new fires are raging in the Amazon rainforest in northern Brazil, official data have showed, amid growing international pressure on President Jair Bolsonaro to put out the worst blazes in years.

The fires in the world's largest rainforest have triggered a global outcry and are dominating the G7 meeting in Biarritz in southern France.

Official figures show 78,383 forest fires were recorded in Brazil so far this year, the highest number of any year since 2013, and experts say the clearing of land during the months-long dry season to make way for crops or grazing has accelerated the deforestation.

More than half of the fires are in the Amazon, and some 1,663 new fires were ignited between Thursday and Friday, according to the National Institute for Space Research (INPE).

The new data came a day after Mr Bolsonaro authorised the deployment of the military to fight the fires and crack down on criminal activities in the region.

The blazes have stirred outrage globally, with thousands protesting in Brazil and Europe yesterday.

US President Donald Trump and UK Prime Minister Boris Johnson, both attending the G7 summit, have offered their countries' assistance in fighting the fires. 

"Any help is welcome in respect to the fires," Brazil's Defence Minister Fernando Azevedo e Silva has told reporters. 

Earlier this week, Mr Bolsonaro blamed the fires on non-government organisations, suggesting they deliberately started them after their funding was cut.

The growing crisis threatens to torpedo a blockbuster trade deal between the European Union and South American countries, including Brazil that took 20 years to negotiate.

EU Council president Donald Tusk has told reporters at the G7 today that it was hard to imagine European countries ratifying a trade pact with the Mercosur bloc as long as Brazil fails to curb the fires ravaging the Amazon, which is considered to be the "lungs of the planet" and crucial to keeping climate change in check.

Why is part of the Amazon burning?

French President Emmanuel Macron, who has taken the lead in piling pressure on Brazil's Bolsonaro over the fires, had earlier accused the far-right leader of lying to him about Brazil's stance on climate change.

Environmental specialists say the fires have been accompanied by increasing deforestation in the Amazon region, which in July quadrupled compared to the same month in 2018, according to data from INPE.

Mr Bolsonaro has previously attacked the institute, describing its data as lies and instigating the sacking of its head.

On Friday, he insisted that the fires should not be used as an excuse to punish Brazil.

"There are forest fires all over the world, and this cannot be used as a pretext for possible international sanctions," Bolsonaro said.

But Brazil's powerful agriculture sector - which strongly supports Mr Bolsonaro - has expressed concerns over the president's rhetoric, fearing boycotts of their products in key markets. 

In an editorial, the respected Folha de S.Paulo newspaper has warned that President Bolsonaro's "bravado" had worsened the crisis caused by accelerating deforestation.

"The damage to (Brazil's) image is done and it could have important trade repercussions," it said.

"Nationalistic bravado will not win the game this time."