Brazil's president, Luiz Inácio Lula da Silva, writing in the Guardian in March, offered us these words of hope: "No country has a larger stake in reversing the impact of global warming than Brazil. That is why it is at the forefront of efforts to come up with solutions that preserve our common future." Lula's words are fine. But we are still waiting for real action.

For the last 10 years, Greenpeace has been working in the Amazon alongside communities to protect the rainforest. Last week, Greenpeace released a report which was the result of a three-year investigation into the role of the cattle industry in driving illegal deforestation in the Brazilian Amazon. The report, Slaughtering the Amazon, reveals the devastating impacts cattle ranching is having on the climate, biodiversity and local communities.

Cattle ranching is the biggest cause of deforestation, not only in the Amazon, but worldwide. The report reveals that the Brazilian government is a silent partner in these crimes by providing loans to and holding shares in the three biggest players – Bertin, JBS and Marfrig – that are driving expansion into the Amazon rainforest.

Greenpeace is now about to enter into negotiations with many of the companies that have either found their supply chain and products contaminated with Amazon leather and beef or who are buying from companies implicated in Amazon deforestation – big brands such as Adidas, Clarks, Nike, Timberland and most of the major UK supermarkets. Meanwhile, back in Brazil, the federal prosecutor in Para state has announced legal action against farms and slaughterhouses that have acted outside of the law. It has sent warning letters to Brazilian companies buying and profiting from the destruction. Bertin and JBS are in the firing line – companies part-owned by the Brazilian government.

While this is a positive step, it's clear that we can't bring about real change and win an end to Amazon destruction for cattle without real action from the government and from big corporations in Europe and the US, who are providing the markets.

Another, worrying example of the widening chasm between rhetoric and reality is a new bill that has just passed through the Brazilian senate. If Lula gives his consent, it will legalise claims to at least 67m hectares of Amazonian land — an area the size of Norway and Germany put together – that is currently held illegally. A second bill, before the Brazilian congress, proposes to more than double the percentage of Amazon rainforest that can be cleared legally within a property. If passed, the effect of both these bills will be to legalise increased deforestation of the Amazon rainforest.

Lula's decision to fund the cattle ranching industry with public money makes no sense when its expansion threatens the very deforestation reduction targets that Lula champions. The laws now waiting for his approval will represent a free ride for illegal loggers and cattle ranchers. It is clear that Brazil now faces a choice about what sort of world leader it wants to be – part of the problem or part of the solution.

Protecting Brazil's rainforest is a critical part of the battle to tackle climate change and must be part of a global deal to protect forests at the climate change talks in Copenhagen at the end of the year. But while world leaders are making speeches, we are losing vast tracts of rainforest. We must also tackle the dirty industries that are driving deforestation if we are to protect the Amazon and the climate for future generations.