BRAZILIAN President Luiz Inacio Lula da Silva said on Thursday that his government had not been successful in trying to negotiate the 50 per cent tariff on Brazilian imports that United States President Donald Trump has threatened to impose.

Washington has ignored Brazil’s attempts to negotiate ahead of the measure’s expected implementation on August 1, the Brazilian leader said.

“Brazil is used to negotiating," Lula said. "On May 16, we sent them a letter asking for clarification on the proposals we had made."

“They didn’t respond. They responded through a website,” Lula said, referring to President Trump’s post on his social media platform Truth Social on July 9, announcing the tariff.

Mr Trump directly linked the import tax to the trial underway in Brazil of his ally, the country’s far-right former President Jair Bolsonaro, which he called a “witch-hunt.”

Rather than backing down, Brazil’s Supreme Court escalated the case, worsening Mr Bolsonaro’s legal troubles. Federal police have raided the former president’s home and political office, ordered him to wear an ankle monitor, banned him from using social media amongst other restrictions.

Lula spoke on Thursday in Vale do Jequitinhonha, one of Brazil’s poorest regions in the state of Minas Gerais, saying he needed to “defend” Brazil’s resources.

In related developments, Brazil’s Vice President Geraldo Alckmin told reporters in the capital, Brasilia, that he had a 50-minute phone call last Saturday with US Commerce Secretary Howard Lutnick.

Mr Alckmin, who also serves as Brazil’s minister of Commerce, Industry and Trade, said: “I reiterated Brazil’s willingness to negotiate — that’s our position.

“Brazil never left the table. We didn’t create this problem, but we want to solve it.”

Separately, Brazil raised concerns on Wednesday at a World Trade Organisation (WTO) meeting.

Brazil’s Ambassador Philip Fox-Drummond Gough said WTO member states are witnessing “an extremely dangerous shift toward the use of tariffs as a tool to interfere in the domestic affairs of third countries.”