An Iranian-American scholar recently released from a notorious prison in Iran still faces charges she endangered the country's national security and has no passport with which to travel abroad, her lawyer said Wednesday.

Although Haleh Esfandiari has the legal right to leave the country, no new passport has been issued since authorities seized hers, attorney and Nobel Peace Prize winner Shirin Ebadi told The Associated Press.

"The next stage is that a date will be set for the trial. I ... will defend her in court," said Ebadi. "I'm certain that my client is innocent and she must be acquitted of the charges."

Esfandiari, director of the Middle East program at the Woodrow Wilson International Center for Scholars, had been held in Evin prison since early May after months of interrogation. Her 93-year-old mother used the deed to her Tehran apartment to post bail late Tuesday, relatives said.

Esfandiari, 67, was in solitary confinement during her four months in the prison and was not allowed access to a lawyer, Ebadi said. Ebadi said she already has filed a complaint with the U.N. Human Rights Council against what she called the "arbitrary" arrest of Esfandiari.

Esfandiari is one of a handful of Iranian-Americans detained or facing security-related charges, adding to the already high tensions between the United States and Iran.

The Iranian Intelligence Ministry had accused Esfandiari and her organization of trying to set up networks of Iranians with the ultimate goal of creating a "soft revolution" in Iran. Her husband, Shaul Bakhash, and the Wilson Center denied the allegations.

Esfandiari, who only weighed 105 pounds to begin with, appeared to have lost weight and had faced significant mental stress while being held, said Lee Hamilton, the head of the Wilson Center.

Her family was not allowed to deliver her medicine, and during brief calls to her mother, Esfandiari said she suffered from arthritis and pain in her eyes, her daughter said.

"Her physical and mental well-being is now the urgent priority," Hamilton said.

Esfandiari told Iranian television Tuesday that she was happy to be released.

"I thank all those who made efforts to make it possible for me to go home," Esfandiari said. The footage showed her walking out of the prison and meeting family members in a car on a nearby street.

Esfandiari was detained Dec. 30 after three masked men holding knives threatened to kill her on her way to Tehran's airport to fly back to the U.S., according to the Wilson Center. The men took her U.S. and Iranian passports, making her unable to leave the country, the center said.

For several weeks, she was interrogated for up to eight hours a day about the activities of the Middle East Program at the Wilson Center, the Washington-based foundation said. Iran charged Esfandiari in May.

Hamilton said he was not sure what prompted Esfandiari's release but that he had recently received a written response from Iranian Supreme Leader Ayatollah Ali Khamenei's office after sending him a letter appealing for her freedom.

Khamenei said he was pleased that Hamilton had expressed a desire for peace and justice and added he had given instructions to "deal with this issue" and that "necessary measures" would be taken, Hamilton said.

Iran has charged three other Iranian-Americans with security-related offenses: Parnaz Azima, a journalist for U.S.-funded Radio Farda; Kian Tajbakhsh, an urban planning consultant with the Soros Foundation's Open Society Institute; and Ali Shakeri, a founding board member of the Center for Citizen Peacebuilding at the University of California, Irvine.

Shakeri and Tajbakhsh are in prison; Azima is free but barred from leaving Iran.