President Luiz Inacio Lula da Silva openly backed the controversial drilling project which began in October when oil giant Petrobras secured a license after a years-long battle.

Raoni Metuktire, the nonagenarian leader of the Kayapo people who rose to fame in the 1980s campaigning against deforestation with British musician Sting, is attending COP30 talks in the Amazon city of Belem.

"I support President Lula, but he must listen to us...He must respect us," Raoni told journalists after taking part in the opening of the People's Summit -- a parallel event to COP30 which aims to give voice to those often not heard in high-level climate negotiations.

"I will make an appointment with him, and, if necessary, I will give him a talking-to so that he listens to me," said Raoni -- instantly recognizable for the large wooden plate in his lower lip.

His comments were translated into Portuguese from his Kayapo language.

The Indigenous leader also highlighted government plans for the Ferrograo railway -- a nearly 1,000-kilometer (620-mile) project to transport grain across Brazil, including through the Amazon -- and ongoing deforestation.

"If these bad actions continue, we will have problems," Raoni said.

A major march for climate is scheduled for Saturday in Belem, where indigenous people and civil society organizations are expected to demand climate justice and the protection of indigenous territories.

- Protests -

UN officials said two security workers were injured when a protest march Tuesday evening resulted in clashes, but Indigenous leaders defended their actions.

"No one committed any acts of banditry -- it was to draw attention," Dona Neves Arara Vermelha, a member of the Arapiuns ethnic group from the COP30 host state of Para, said at the press conference.

The Arapiuns grievances include a land demarcation process they deem too slow and insufficient forest protections to counter the encroaching interests of the powerful agribusiness sector.

"We still hope to have a discussion with President Lula, with the leaders...to sit at the negotiation table. They refuse to listen to what we are saying here," added Aracelia Arapiun, another Indigenous woman.

Amazon deforestation has steadily declined since Lula's return to power, after having increased sharply under the presidency of his far-right predecessor Jair Bolsonaro.

Raoni was one of the figures who symbolically presented Lula with the presidential sash during his inauguration for a third term in 2023.

Lula has repeatedly stated his belief that the world is not ready to move away from fossil fuels, and that expanding oil production in Brazil -- the world's eighth largest producer -- will help finance the energy transition.

However, at a leaders' summit last week ahead of COP30, he warned that "Earth can no longer sustain the development model based on the intensive use of fossil fuels."