Palestinian prisoner Khader Adnan ended a 56-day hunger strike on Sunday after Israel agreed to release him, his lawyer and the Palestinian Prisoners Club announced.
Adnan, 37, has been held for a year under administrative detention, which allows imprisonment without charge for renewable periods of six months indefinitely.
His hunger strike, which had brought him near death, had sparked warnings from the Palestinian government that it held Israel responsible for his fate.
"Khader Adnan ended his hunger strike last night, after an agreement was reached to release him on July 12," his lawyer Jawad Boulos said.
He said doctors at the Israeli hospital he was transferred to were considering ways to start feeding him.
The Palestinian Prisoners Club confirmed that Mr Adnan had ended his hunger strike.
An Israeli official confirmed Adnan would be set free on July 12, telling AFP the deal was made possible after Adnan withdrew his demand that Israel undertake never again to place him under administrative detention.
The official said Adnan's deteriorating health and appeals from the International Committee of the Red Cross and the Palestinian Authority had contributed to the decision to release him.
Adnan was detained a year ago.
An Israeli security official told AFP that Adnan was "a member of Islamic Jihad," a Palestinian militant group.
He had previously gone on hunger strike for 66 days in 2012 to protest against his detention. He was released at the end of the strike, during which he had ingested vitamins and salt.
This time, he refused to swallow anything except water.
The Palestinian government had warned it held Israel responsible for his fate, while the Israeli government in mid-June renewed efforts for legislation that would allow prisoners to be force-fed when their lives are in danger.
The Palestinian leadership submitted a report to the International Criminal Court last week that included the treatment of Palestinian prisoners in Israeli jails.
*This story was edited by Ahram Online.