Brazilian authorities will exhume the remains of late President Joao Goulart to determine whether his 1976 death in exile was a murder committed on orders from the country's 1964-1985 military regime, officials said Tuesday.

The exhumation "might turn out to be decisive in clarifying the real circumstances that resulted in the death of Jango (as Goulart was known)," the presidential Office of Human Rights said.

"It is an historic moment not just for the family, but for the country and for all the families of people killed, disappeared, tortured and exiled by the military dictatorship," Joao Marcelo Goulart, a grandson of the late head of state, said.

The left-leaning Jango Goulart was toppled by the Brazilian armed forces in 1964 with the U.S. government's blessing.

The ousted president, who had a history of heart problems, died in 1976 at a hotel in Mercedes, Argentina.

The official cause of death was a heart attack, but authorities in Argentina and Brazil - where Goulart was buried - prevented an autopsy.

Around five years ago, a former Uruguayan spy serving a prison sentence in Brazil for arms smuggling came forward to say that Goulart was poisoned.

The assassination was carried out under the aegis of Plan Condor, a joint operation of the military regimes that controlled much of South America in the 1970s, according to Mario Neira Barreiro.

He said Uruguayan intelligence operatives killed Goulart by replacing his normal heart medication "with pills having a contrary effect."

Media outlets are reporting that Goulart's remains will be received in Brasilia will full honors at a ceremony including President Dilma Rousseff and several of her predecessors.

"That is very important for the family. Thirty-seven years after his death, Jango returns to Brasilia as head of state, with the honors they always denied to him," Joao Marcelo Goulart said. EFE