The Brazilian Senate has passed a forestry reform bill which is backed by the country's powerful agribusiness sector but opposed by environmentalists who see it as a threat to preservation of the Amazon.

The legislation, which received 59 votes in favor and seven against in an overnight vote, still has to be approved by the Chamber of Deputies before being submitted to President Dilma Rousseff.

The current forestry code, which dates back to 1965, limits the use of lands for farming and mandates that up to 80 percent of the Amazon, the world's largest tropical rainforest, remain intact.

"This shameful vote legalizes environmental crime," said Senator Marinor Brito in explaining her no vote.

Speaking from Durban on the sidelines of a UN-sponsored climate change talks, Marina Silva, who ran as the candidate of Brazil's small Green Party in last year's presidential election, also slammed Senate approval of the reform.

"The bill that was approved yesterday by the Senate undermines protection of the forest, provides amnesty for those who deforest and will increase deforestation", she told a press conference.

"Our only hope is President Dilma, who during the election campaign had pledged to veto any measure which might increase deforestation or amnesty those who engage in deforestation," said Silva, who served as environment minister under former president Luiz Inacio Lula da Silva.

But the agrobusiness sector, which has a large representation in Congress, defends the reform, stressing the need to extend farm land to bolster Brazil's food security.

"With this, we are ending the confrontation between environmentalists and farmers," said Senator Jorge Viana, a sponsor of the bill, pointing out that the text strikes a balance between farm development and environmental conservation.

But ecologists are fiercely opposed to the reform, fearing an irreversible impact on government commitments to combat deforestation and global warming.

The new Forestry Code would reduce the area which must be preserved, protected and reforested and would effectively lift sanctions and obligations that were imposed on rural landowners under the 1965 code.

It would threaten 690,000 square kilometers (266,000 square miles) of forest, an area bigger than France, and prevent Brazil from meeting its target of reducing deforestation by 80 percent, environmentalists have warned.

Brazil said Monday that the pace of deforestation in its Amazon region fell to its lowest level since authorities began monitoring in 1988.