Jean Charles de Menezes, 27, was killed on 22 July by anti-terror officers as he boarded a subway train in south London, one day after a failed attempt to repeat the 7 July attacks, which killed 52 commuters and four suspected bombers.
The shooting left de Menezes's family outraged after leaked information on an investigation into his death revealed that he had not been acting suspiciously as they had initially been led to believe.
Brazil sent Wagner Goncalves, from the attorney general's department, and Marcio Pereira Pinto Garcia, from the department of international judicial cooperation at the Ministry of Justice, to seek clarification about the reports leaked to ITV television last week.
The delegation will meet John Yates, deputy assistant commissioner of the Metropolitan Police, members of the Independent Police Complaints Commission (IPCC) - which is investigating the killing - and other officials.
"The Brazilian government anticipates receiving clarification regarding a number of matters, including the information released by the press in recent days," a statement on its London embassy's website said.
Supporters of de Menezes, who have put tremendous pressure on the Metropolitan Police and called for its chief, Sir Ian Blair, to resign, are to hold a vigil outside Prime Minister Tony Blair's offices in Downing Street later in the day to mark the one-month anniversary of the young man's death.
Police Commissioner Ian Blair (R)
is under pressure to step down
At the demonstration by the Jean Charles de Menezes Family Campaign group, the electrician's cousin Alessandro Pereira will hand in a letter addressed to the prime minister, calling for a public inquiry.
Speaking to the BBC in Brazil, de Menezes's mother, Maria Otoni, urged that those who pulled the trigger be punished.
"They took my son's life. I am suffering because of that. I want the policeman who did that punished. They ended not only my son's life but mine as well," she said, weeping.
Controversies surrounding the killing grew over the weekend when a newspaper reported that the surveillance officers who followed de Menezes into Stockwell subway station did not feel he was armed or about to set off a bomb.
They wanted to detain the electrician but were instructed to hand over the operation to a team of armed police who then shot him seven times in the head and once in the shoulder, The Observer reported.
Alessandro Pereira (C), cousin of
de Menezes, calls for public inquiry
Commissioner Blair, who has denied allegations of a cover-up, said in an interview with the News of the World Sunday weekly that 24 hours passed before he learned de Menezes was innocent, after he publicly linked the killing to the ongoing anti-terrorist operation.
Deputy Prime Minister John Prescott, meanwhile, backed the nation's most senior police officer, telling the BBC simply "yes" when asked if Blair enjoyed his "full and unqualified" confidence.