Fujimori tried to resign the presidency by sending a fax from Japan, but Peru's congress did not accept it, and instead declared him morally unfit to govern.
He has so far been shielded from extradition attempts by his Japanese citizenship -- Japan says its nationals should be subject to Japanese law -- and by the fact the two countries have no extradition treaty.
Japan granted the former Peruvian leader nationality on the grounds that his parents, who emigrated to Peru where he was born, were Japanese.
Earlier this week, Fujimori posted a political manifesto on his Web site, announcing the formation of a new political movement, "Si Cumple," in an apparent bid to return to Peru for the 2006 presidential election.
"The time has come for the great Fujimorista counterattack, in order to put Peru back again in the road of order, peace, stability and progress," he wrote.
In September 2001, Peru issued an international arrest warrant for Fujimori on charges of murder, serious injury and forced disappearance in the cases of 25 people allegedly killed by paramilitary death squads in the early 1990s.
Japan declined Interpol's request for Fujimori's arrest and extradition in March this year.
Peru's embassy said a spokesman for the Japanese government told them, there was "no compelling reason to honor it in light of domestic law."