More than 100 prominent Germans have signed an open letter to the Iranian government, calling for the release of two German journalists.
The two were arrested in October while interviewing the son of Sakineh Mohammadi Ashtiani, 43, sentenced to death by stoning for adultery.
German foreign minister Guido Westerwelle and footballer Franz Beckenbauer were among the signatories.
On Saturday, Ashtiani said she planned to sue the German journalists.
She told reporters at a news conference in the north-western city of Tabriz that the journalists had "embarrassed" her, but did not elaborate.
Also on the list of those appealing for the release of the two journalists from the Bild am Sonntag newspaper were film director Volker Schloendorff and the head of the Islamic Council of Germany, Ali Kizilkaya.
Mr Schloendorff, who has officiated at Iranian film festivals as a jury president, said he loved Tehran but no longer wanted to travel there because of the imprisonment of the two journalists and other cases.
Finance minister Wolfgang Schaeuble, defence minister Karl Theodor zu Guttenberg, tennis player Boris Becker and a winner of the Nobel Prize for literature, Herta Mueller, also signed the letter.
The two journalists were arrested in Tabriz after reportedly interviewing Ashtiani's son, Sajjad Ghaderzadeh.
Iran says the Germans entered the country illegally, on tourist visas and did not obtain the accreditation required for journalists.
At her news conference on Saturday, Ashtiani said she had told her son to sue the Germans, as well as her former lawyer and the man convicted of her husband's murder.
Ashtiani was convicted in 2006 of adultery and sentenced to death by stoning.
Her sentence was commuted last year but she could still be hanged for her husband's murder.
Last month, Ashtiani was filmed confessing to her part in the murder and taking part in a re-enactment, which was shown on Iranian TV.
However, campaigners have cast doubt on the validity of her confession.
Ashtiani told reporters that she was not tortured while in prison, saying: "These are all rumours".
She also criticised Mina Ahadi, an anti-stoning activist based in Germany who has campaigned for her release.
Ms Ahadi responded by saying she believed Ashtiani was being subjected to "enormous pressure by the Islamic regime", according to the AFP news agency.
The deputy editor of the Bild am Sonntag, Michael Backhaus, said he found it "strange that a woman who has been condemned to death in Iran, is allowed to leave prison for a few hours to tell Western media that she wants to denounce the journalists who want to report on her case".