Boris Johnson said he is “horrified” by the devastation in the Amazon, but warned against using the destruction of the rainforest to block trade deals.

French President Emmanuel Macron has indicated he could block an EU trade deal with Brazil and its neighbours over Jair Bolsonaro’s country’s handling of fires in the rainforest.

Irish premier Leo Varadkar has also said he would not back the EU-Mercosur agreement if Brazil did not honour its environmental commitments.

But Mr Johnson cautioned against the approach at a “very difficult time for global free trade”.

Mr Macron has put the situation in the Amazon on the agenda at the G7 summit he is hosting in Biarritz.

Mr Johnson said he is “horrified by what is happening in the Amazon basin” and the UK “stands ready to help in any way that we can to extinguish the fires and to protect habitat and biodiversity”.

But he added: “I think I’d be reluctant to do anything, at this very difficult time for global free trade, to cancel another trade deal.”