In an opinion piece published in the New York Times, Lula dismissed the description by US President Donald Trump of the trial as a “witch hunt”, saying that it was a “historic decision which safeguard’s our institutions and the democratic rule of law”.

The Brazilian leader said he had written the essay to establish an open and frank dialogue with US President Donald Trump, who has imposed 50% tariffs on Brazilian imports.

Lula called the tariff hike “not only misguided but illogical”.

Relations have been tense between the US and Brazil in recent months, in stark contrast to the times when Trump’s counterpart in Brazil was Jair Bolsonaro.

Bolsonaro often expressed his admiration for Trump, who hosted him at his Mar-a Lago resort in 2020.

Lula, a left-wing leader, who is known for his direct tone, did not mince his words in his New York Times editorial.

He said that over the past 15 years the US had “accumulated a surplus of $410bn (£302bn) in bilateral trade in goods and services”, adding the decision to impose the tariffs could only be political.

“The US government is using tariffs and the Magnitsky Act to seek impunity for former President Jair Bolsonaro,” Lula wrote, referring to the sanctions which the US has imposed on the Supreme Court justice who led the trial against Bolsonaro.

The trial concluded on Thursday when four out of the five Supreme Court justices on the panel tasked with judging Bolsonaro found him guilty of all five charges he was facing. A simple majority was needed to convict him.

Bolsonaro has been sentenced to 27 years and 3 months in prison – a sentence which his lawyers say they will appeal against.

Trump said he found the verdict “very surprising” and US Secretary of State Marco Rubio announced that the US would “respond accordingly to this witch hunt”.

In his New York Times article, Lula insisted the trial was “not a ‘witch hunt'”.

“The judgement was the result of proceedings carried out in accordance with Brazil’s 1988 Constitution, enacted after two decades of struggle against a military dictatorship,” he wrote, reminding readers that Brazil’s democracy was restored in 1985 after 20 years of military rule.

Lula also dismissed the Trump administration’s accusations that Brazil’s justice system had targeted and censored US tech firms.

The Brazilian president said that his country’s courts were right to regulate the internet and that US firms were not being treated unfairly.

He concluded his essay by addressing President Trump directly, telling his US counterpart that Brazil remains open to negotiating “anything that can bring mutual benefits”, but warned Trump that “Brazil’s democracy and sovereignty are not on the table”.

The 79-year-old appeared alongside his medical team at a news conference at Sírio-Libanês hospital in São Paulo.

“This here is not an interview, this is simply a session to say thanks. To thank, firstly, God, who has looked after me in a very generous manner,” he said.

Lula was taken to hospital on Monday after he had complained of a severe headache.

Doctors performed a craniotomy on the president, a procedure in which part of the bone is surgically removed from the skull to treat the bleed and relieve the pressure. The bone is then replaced.

The brain bleed, or intracranial haemorrhage, was caused by a blow to the head he sustained when he fell in his bathroom at the presidential residence in October, according to a hospital statement.

“Thank you very much for the prayers,” Lula added on Sunday. “And for those who only have hate, you’re forgiven. I am here, alive, whole, and with more desire to work.”

On Tuesday, doctors said the president was in a stable condition following the surgery and was conscious.

Lula was “lucid” and conversing with medical staff, they added.

They also insisted that he had not sustained any brain injury and was not experiencing and after-effects from the surgery.

Asked when he would return to the capital, doctors had said that if everything went well, they expected Lula to be back in Brasilia “next week”.

While Lula was in hospital, Vice-President Geraldo Alckmin took on some of the president’s commitments.

The doctors said the bleeding was a result of the fall Lula had sustained in October.

They explained that it was not unusual for problems from a blow to the head to appear “months later”.

Lula had slipped in the bathroom in the Alvorada Palace on 19 October and hit the back of his head. On Sunday, he explained he had been cutting his toe nails at the time and had been sitting down.

He went on to have five stitches. On his doctors’ advice, the president cancelled his planned trip to Russia for a summit of the Brics countries.

He returned to full duties days later.Lula has been in power since January last year after narrowly beating the incumbent, Jair Bolsonaro, in a bitterly fought election.

During the election campaign, he often joked that he had “the energy of a 30-year-old”.

Lula’s personal doctor, Roberto Kalil, said during a news conference on Thursday that the follow-up procedure to block blood flow to the affected area was a “success”.

“The president is awake and speaking,” Kalil told reporters at the Hospital Sirio-Libanes in Sao Paulo where Lula, 79, is being treated.

The president was transported to the hospital from the capital Brasilia earlier this week after he experienced headaches that his doctors linked to a recent fall.

Lula, who was sworn in as president in early 2023, had curtailed travel in recent months after he suffered trauma to the back of his head when he fell at home in late October.

The left-wing leader hit his head after falling in a bathroom at the presidential residence and received several stitches.

On Thursday, Lula’s doctors stressed that he was doing well physically and mentally, and should soon be able to return to his duties.

Durring the latest surgery, doctors inserted a catheter in Lula’s femoral artery to block blood flow going through the middle meningeal artery in his head, to minimise the risk of a haemorrhage reoccurring.

Kalil described the procedure as “routine” and “minimally invasive”, carried out under sedation rather than anaesthesia. The catheter was likely to be removed later on Thursday.

“If everything continues as it is, at the beginning of next week the president should be discharged” from the Sao Paulo hospital, Kalil said.

“He will gradually resume his normal activity,” the doctor added, noting that although Lula would be able to work, his convalescence would still require “relative rest over several weeks”.

Neurologist Rogerio Tuma also said on Thursday that the Brazilian president’s “neurological examination is normal”.

“He is very well,” Tuma added, but “he should not exert himself physically or mentally.”

Doctors at the Sirio-Libanes hospital in Sao Paulo, Brazil, announced on Wednesday that the minimally invasive procedure would take place the following morning.

Called a middle meningeal artery embolisation, the procedure allows medical professionals to enter a patient’s blood vessels using small tubes. The aim is to insert a small blockage to prevent bleeding from the artery, located on the outside of the brain.This new procedure follows a two-hour surgery Lula, 79, underwent on Tuesday to treat health problems stemming from a fall at home in late October. He had been rushed to the hospital overnight.

After Tuesday’s surgery, the Brazilian leader was scheduled to remain in intensive care for a period of about 48 hours. Despite the new procedure on Thursday, doctors emphasised Lula was lucid and recovering.

“He underwent physiotherapy, walked and received visits from family members,” the doctors said in a statement, noting that he had “spent the day well” and is in good condition.

Lula’s personal doctor, Roberto Kalil Filho, also told reporters on Wednesday that the procedure is “relatively simple” and “low risk”, taking no more than one hour.

“We waited to see that the president was recovering well before deciding to go ahead with the procedure,” he said.

Nevertheless, Lula’s recent medical interventions have raised concerns about his health.

Lula, who is currently about halfway through his current term as president, is considered Brazil’s oldest sitting president. He was sworn in for his third term in January 2023, at age 77 — and now, at 79 years old, he surpassed the previous record holder, Michel Temer, who was 78 when he left office.

Doctors say Lula will return to the capital of Brasilia at the beginning of next week, with no aftereffects anticipated following the two procedures. Lula’s vice president, Geraldo Alckmin, has been recalled to Brasilia to fill in for official duties.

Meanwhile, a gathering of supporters met in Brasilia on Tuesday to offer their support for the popular leftist president, who previously served as president from 2003 through 2011.

One man dressed as Santa Claus held up a sign of Lula with the caption “Saúde presidente” — a wish for good health, written in Portuguese

The 79-year-old was taken to hospital in the capital, Brasília, on Monday after he had complained of a severe headache.

An MRI scan revealed the bleed and Lula was transferred to the renowned Sírio-Libanês hospital in São Paulo to have it drained.

The intracranial haemorrhage was caused by a blow to the head he sustained when he fell in his bathroom at the presidential residence in October, according to a hospital statement.

Doctors said they had performed a craniotomy on the president, a procedure in which part of the bone is surgically removed from the skull to treat the bleed and relieve the pressure. The bone is then replaced.

In a news conference on Tuesday morning local time, the doctors said that the president was in a stable condition following the surgery and was conscious.

They said Lula was “lucid” and conversing with medical staff.

They also insisted that he had not sustained any brain injury and was not experiencing and after-effects from the surgery.

Asked when he would return to the capital, doctors said that if everything went well, they expected Lula to be back in Brasilia “next week”.

Earlier, the presidential spokesman, Paulo Pimenta, had said that Lula would likely remain in the intensive care unit for another 48 hours.

“He is stable, conscious and calm,” Mr Pimenta said.

While Lula is in hospital, Vice-President Geraldo Alckmin will take on some of the president’s commitments, including welcoming Slovak Prime Minister Robert Fico, who is due to arrive in Brazil later today.

The doctors said the bleeding was a result of the fall Lula had sustained in October.

They explained that it was not unusual for problems from a blow to the head to appear “months later”.

Lula had slipped in the bathroom in the Alvorada Palace on 19 October and hit the back of his head.

He had to have five stitches and, on his doctors’ advice, cancelled his planned trip to Russia for a summit of the Brics countries.

He returned to full duties days later.

Lula has been in power since 1 January 2023 after narrowly beating the incumbent, Jair Bolsonaro, in a bitterly fought election.

During the election campaign, he often joked that he had “the energy of a 30-year-old”.