A Palestinian prisoner who has been detained by Israeli authorities without charge has agreed to end a 66-day hunger strike in a deal that will see his release within two months.

Israel’s justice ministry said that Khader Adnan will remain in custody until April 17, when his administrative detention will expire, provided that no new additional substantial evidence arises against him.

Adnan, 33, commenced his hunger strike in December, one day after his arrest in village of Arabah in the West Bank. The Israeli military said he had been detained for activities that threaten regional security.

Under Israeli laws, such an inmate can be held indefinitely without trial or even formal charges.

A local rights group called al-Haq estimated that 315 Palestinians are currently being detained under this practice.

Israel believes he is the leader of a group called Islamic Jihad, which is designated as a terrorist organization.

While Adnan has served as a spokesman for the group, it’s not clear if he ever participated in any of their violent attacks against Israelis.

Through his lawyer, Adnan claimed he was arrested violently and subjected to humiliating interrogation sessions while under detention.

An Israeli group called Physicians for Human Rights warned that Adnan was in immediate danger of death, and that he had suffered significant muscular atrophy.

The European Union (EU) has also expressed concern about Adnan’s treatment at the hands of Israeli security forces.

Catherine Ashton, the EU’ foreign policy chief, said in a statement: Detainees have the right to be informed about the charges underlying any detention and be subject to a fair trial.”

She also emphasized the EU's long-standing concern about the extensive use by Israel of administrative detention without formal charge.

Thousands of Palestinians have rallied in the West Bank and Gaza City demanding Adnan’s immediate release.