Three Palestinians imprisoned by Israel without trial agreed on Wednesday to end more than two months of hunger strike after dates were set for their release, a Palestinian NGO said.

Brothers Mohammed, 25, and Mahmud Balbul, 23, as well as 19-year-old Malek al-Qadi "suspended their hunger strikes following an agreement which sets an end to their detention and dates for their release," the Ramallah-based Palestinian Prisoners Club said.

The Palestinian Authority said that Al-Qadi would be freed on Thursday and the Balbul brothers on December 8.

The brothers were arrested in June and have been refusing to eat for 78 days.

Al-Qadi was detained in June and has been fasting for 70 days.

Their hunger strikes were in protest against their internment under Israel's controversial administrative detention law, which allows suspects to be held for renewable six-month periods without being charged.

Al-Qadi's 16-year-old sister Umaya told AFP recently that her brother faced "imminent death."

Several Palestinian internees have staged hunger strikes in recent months. All called off their protests after being given reassurances that their detention would not be renewed.

The UN and Palestinian prisoners' rights groups say that the Israeli military court system in place in the Israeli-occupied West Bank is increasingly imposing administrative detention.

There are around 7,000 Palestinian prisoners held by Israel, of whom about 700 are under administrative detention.

"This is the highest number of administrative detainees at a given time since early 2008," a spokeswoman for the UN High Commissioner for Human Rights said last month.