Brasília (AFP) - Brazilian President Jair Bolsonaro canceled a ban on sugarcane farming in the country's Amazon and Pantanal tropical wetlands Wednesday, a move that environmentalists say threatens the ecologically vulnerable regions.

The ban on the crop, which Brazil uses to make ethanol, had been put in place under a 2009 decree, which Bolsonaro and his economic and agriculture ministers overturned.

By repealing the measure, the government "exposes two fragile ecological areas to the predatory and economically unjustifiable expansion of cane and throws away the international sustainability image that Brazilian ethanol built with difficulty," said Observatorio do Clima, a coalition of local environment groups.

Brazil's Agriculture Ministry denied that the move undermines preservation of the Amazon and Pantanal, and said the 2009 rule was obsolete, because other laws had since been passed protecting those areas.

The Sugarcane Industry Union (UNICA) said that the 2009 rule was nothing more than "bureaucratic scaffolding" adding that "ethanol and all our products must be sustainable from beginning to end."

Brazil is the world's largest sugarcane producer, with more than 10 million hectares (24.7 million acres) planted in 2018, according to data from UNICA.

The ban on planting sugarcane in the Amazon and Pantanal was implemented under the government of former leftist leader Luiz Inacio Lula da Silva (2003-2010).

It was meant to discourage planting of the crop in those areas out of fear that sugarcane would cause deforestation and take up land suitable for food cultivation.