A hearing due Thursday of 97-year-old Laszlo Csatary, who tops the Simon Wiesenthal Center's dwindling wanted-list of suspected Nazi war criminals, was deferred to next week, lawyers said.
Csatary's lawyer and prosecutors did not specify a date nor explain the delay.
"The hearing will take place in a week," his lawyer Gabor Horvath told AFP.
Csatary -- accused by the Wiesenthal Center of organising the World War II deportation to their deaths of some 16,000 Jews from the ghetto of Kosice in present-day southeast Slovakia -- has protested his innocence.
He was arrested in Budapest on July 18 and then placed under house arrest. Slovakia's Jewish community has said he should stand trial on Slovak soil.
Csatary, full name Laszlo Csizsik-Csatary, helped run the Jewish ghetto in Kosice, a town that was visited in April 1944 by Adolf Eichmann, a key figure in the Nazis' Final Solution, the Wiesenthal Center says.
While there between 1941 and 1944, Csatary beat and brutalized Jews and sent 16,000 to their deaths in Ukraine and to the gas chambers at the Auschwitz extermination camp, it said.
In 1948, a court in what was then Czechoslovakia condemned Csatary to death in absentia, but he made it to Canada where he lived and worked as an art dealer before being stripped of his citizenship there in the 1990s.
He ended up in Budapest where he lived freely, until the Wiesenthal Center alerted Hungarian authorities last year.