A statement signed by 15 Tunisian and international human rights groups has opposed the plan to extradite Libya's former prime minister back to Tripoli.
Human Rights Watch, Amnesty International and the Tunisian League for the Defense of Human Rights were among the groups saying that Al-Baghdadi Al-Mahmoudi risked death or torture if returned to Libya.
The 70-year-old former Libyan prime minister was arrested in southern Tunisia last September trying to cross into Algeria.
Libyans want to prosecute him for crimes committed under the regime of Moammar Gadhafi.
Friday's statement called on President Moncef Marzouki, a former rights activist himself, not to sign the extradition decision ordered by the court in the absence of guarantees for Al-Mahmoudi's safety and a fair trial.