LIMA, Peru: Peru's top court has reinstated a controversial pardon for former President Alberto Fujimori, who governed the country in the 1990s before being sentenced for participating in human rights violations.

Fujimori, 83, was initially pardoned in 2017 after 10 years in prison. However, that decision was overturned a few months later after the intervention of an international court.

Jo-Marie Burt, senior fellow at the Washington Office on Latin America, said the latest ruling opens the door for the pardon to be again appealed in the Costa Rica-based Inter-American Court of Human Rights, although a new decision could take months to be announced.

"The organizations that represent the victims in Peru have already called upon the Inter-American Court to have a meeting and to review this decision. They actually filed the request yesterday," Burt told Reuters.

Fujimori's lawyer Cesar Nakazaki said he might leave prison as early as this week.

"I have just spoken with President Fujimori, he has felt great relief. It was unfair for him to die in prison," Nakazaki told reporters.

After the ruling, leftist President Pedro Castillo called on international courts to "protect the effective practice of justice."

Also, left-wing groups called for protests. The first pardon prompted thousands to take to the streets.

Fujimori was pardoned in 2017 by then-President Pedro Pablo Kuczynski, a former Wall Street banker who, at the time, needed congressional support to survive an impeachment attempt.

Representatives for Kuczynski were proven to have lobbied part of the Fujimorista Popular Force bloc in Congress, possibly to swap votes for Fujimori's pardon, fueling anger over the decision to free him.

Human rights groups took their challenge to the Inter-American Court of Human Rights, which ordered a local court to revise the decision.

The local court then ruled to null the pardon, and Fujimori returned to prison after being free for some nine months.

Burt said she expects the Inter-American Court to again issue a similar decision, but Nakazaki said he thought the pardon could survive the challenge.

Fujimori resigned the presidency in 2000, after starting a third term. When a series of videos showed Fujimori's spy chief bribing politicians with cash, he flew to Japan and submitted his resignation by fax.

After claiming citizenship in Japan and remaining there for several years before flying to Chile in 2005, where he was arrested and later extradited to Peru.