Some Greenpeace activists protested in front of the Brazilian government headquarters on Tuesday, demanding Brazil present a zero deforestation proposal at the upcoming United Nations' Climate Change Conference in Copenhagen.

The activists called on Brazilian President Luiz Inacio Lula da Silva to present a concrete proposal for tackling the impact of global warming at the UN conference.

"Greenpeace came here to demand from the Brazilian government an active stance in the fight against climate changes. We want zero deforestation, renewable energy and protection of the oceans," said Joao Talocchi, Greenpeace's climate campaigner.

Brazil should reduce its carbon emissions as well, he added.

According to Talocchi, the first step is to set a goal of zero deforestation in the Amazon rainforest region by 2015. His proposal is much tougher than the Brazilian government's, which foresees an 80 percent deforestation reduction by 2020.

The government's plan, which is considered bold and praised by several world leaders, is deemed insufficient by Greenpeace, as it leaves room for over 1.5 billion trees to be cut down in the next decade.

"Brazil cannot allow 5,000 hectares of forest to be destroyed every year," Talocchi said .

When the Greenpeace activists protested, President Lula was discussing with his ministers the proposal to be presented in Copenhagen. A government official met with the protesters, and promised that their proposals would be sent to the president.

Greenpeace is a non-governmental organization for the protection and conservation of the environment.