Brazilian President Jair Bolsonaro has said it is a “lie” that fires are ravaging the Amazon rainforest, despite data from his own government showing the number of blazes is rising.

The far-right leader has faced international condemnation for presiding over huge fires and rising deforestation in the Amazon – criticism he took issue with in a speech to a video conference of countries that share the world’s biggest rainforest.

“Tropical rainforest doesn’t catch fire. So this story that the Amazon is burning is a lie and we have to fight it with real numbers,” he said on Tuesday.

Bolsonaro last year similarly denied a spike in fires that provoked a global outcry, trading barbs with French President Emmanuel Macron and other world leaders.

Fires in Brazil’s Amazon for the month of August hit a nine-year high in 2019 and this month so far looks even worse. More than 10,000 fires have been recorded in the first 10 days of August, up 17 percent from the same period a year ago, according to data from the country’s national space research agency Inpe.

Experts say the fires are typically not sparked naturally, but set by humans to clear land illegally for farming and grazing.

Last year, huge fires devastated the Amazon from May to October, sending a thick haze of black smoke to Sao Paulo, thousands of kilometres away.

The fires triggered worldwide alarm over a forest seen as vital to curbing climate change.

Experts warn this year’s dry season, which is just getting started, could see even more fires.

Foreign pressure is mounting on Brazil to protect the world’s largest rainforest, an ecosystem vital to preserving climate change because of the vast amount of carbon dioxide that it absorbs.

Global investors managing more than $2 trillion have threatened to pull their investments out of Brazil’s meatpackers, grains traders and government bonds if Bolsonaro’s administration does not take action on Amazon destruction.