"He hasn't appealed, the decision is final since the 1st of April," the prosecutor in charge of the case, Agnetha Hilding Qvarnström, told AFP.
"Then according to the law the Polish authorities have 10 days to come and get him, so the 10th of April is the last day to come and get him," she added.
"We keep him here in Stockholm until they come and get him ... but I can confirm that he's still in Stockholm."
Högström, 34, was arrested on February 11th over the theft of the "Arbeit Macht Frei" sign which disappeared on December 18 from over the gate of the notorious World War II camp set up in occupied Poland by Nazi Germany.
On March 11th, a Stockholm court allowed his extradition to Poland to face trial for the theft.
Högström in 1994 founded the National Socialist Front, a Swedish neo-Nazi movement he headed for five years before quitting.
He has told Swedish media he was supposed to act as an intermediary to pick up the sign and sell it to a buyer, but claimed that he ended up informing Polish police about the people behind the plot.
Polish police recovered the five-metre metal sign, whose German inscription means "Work Will Set You Free", on December 20, two days after the theft. They arrested and charged five Polish men.
The sign, which had been cut into three parts, was returned by investigators to the Auschwitz museum on January 21, less than a week before commemorations marking the 65th anniversary of the camp's liberation by Soviet Russian troops.
The sign has long symbolised the horror of the camp where some 1.1 million people - one million of them Jews - were victims of Nazi German genocide from 1940 to 1945.
Polish judicial authorities indicted Högström in January and issued a European arrest warrant for him on February 2, after Sweden provided additional information on his place of birth, parents' names and residence.
The Local Sweden
