BIARRITZ: EU Council president Donald Tusk said Saturday it was hard to imagine the bloc ratifying its trade pact with South America's Mercosur grouping as long as Brazil fails to curb the fires ravaging the Amazon rainforest.

The European Union "stands by the EU-Mercosur agreement", Tusk told reporters at a G7 meeting in Biarritz in southern France.

"But it is hard to imagine a harmonious process of ratification by the European countries as long as the Brazilian government allows for the destruction of the green lungs of planet earth," he added.

Tusk also the EU was ready to offer financial help to fight the fires.

French President Emmanuel Macron has said the G7 should hold emergency talks on the Amazon fires, taking the lead in piling pressure on Brazil's far-right leader Jair Bolsonaro.

He and Irish leader Leo Varadkar have both pledged to block a new trade deal between the EU and Latin American trading bloc Mercosur, which includes Brazil.