Peru’s Justice Minister Daniel Figallo said on Friday that Fujimori’s health problems were not serious enough to warrant a pardon.
The president had"decided not to exercise his authority to grant a humanitarian pardon," Figallo said.
"Fujimori does not have a terminal illness, neither does he have a serious, incurable degenerative illness," Figallo said. "Neither does he have serious incurable mental disorders."
The 74-year-old, who was president from 1990 to 2000, had been treated for cancerous lesions on his tongue while he was in prison. A medical panel said in March there was no evidence the cancer had returned.
Fujimori was convicted of the killings of 25 people through a government-backed death squad during Peru’s battle against the rebels from the Maoist group Shining Path.
Supporters of Fujimori still retain political influence in the country’s Congress, with long-standing rumors of a secret deal to secure his release.
Election defeat for daughter
Humala beat Fujimori’s daughter, the former lawmaker Keiko Fujimori, in a presidential election runoff in June 2011.
The Fujimori family asked Humala for the humanitarian pardon last October, citing their father's failing health. Humala had already said ahead of the decision that he would not be pressured "through the media or with diatribes" into granting the pardon.
During a corruption scandal in the final days of his presidency, Fujimori escaped Peru and fled to his parents’ native Japan. He resigned by fax from a Tokyo hotel.
He was arrested during a visit to Chile and extradited to Peru to face charges in September 2007.
The request reopened old wounds in the country, where some 70,000 people died in the guerrilla war with Shining Path during the 1980s and 1990s.
rc/dr (AFP, AP, Reuters)