Jerusalem (CNN) -- Negotiations to end a mass hunger strike by up to 2,000 Palestinians detained by Israel are making progress and a resolution may be only days away, Palestinian officials said Saturday.
The talks over the detainee demands involve Palestinians, Israeli officials and Egyptian mediators.
"We have been informed by the Egyptian mediators that there is a very close deal to be reached in the coming hours or maybe by tomorrow," said Khaled al-Batsh, an Islamic Jihad leader and spokesman.
Between 1,600 and 2,000 Palestinians are protesting prison conditions and administrative detention, a controversial Israeli military practice that allows authorities to detain people indefinitely.
Hassan Abed Rabo, a spokesman for the Palestinian Ministry of Detainees and ex-Detainees, told CNN he was aware of progress in the negotiations, but did not know the details.
The head of the Palestinian Prisoner Association Club, Qadoura Fares, said a deal had not been reached, but pressure to resolve the standoff included American and European officials.
A senior Israeli official on Saturday would say only that talks to end the impasse were ongoing.
Israel's high court on Monday rejected an appeal requesting the release of two Palestinian prisoners who have been on a hunger strike for nearly two and a half months, an attorney representing them said.
Judges ruled that the two men, Bilal Diab and Tha'er Halahlah, remained a security risk to Israel, and that their hunger strike was not a reason to release them from administrative detention, according to lawyer Jamil al-Khatib.
"If any harm happens to the prisoners especially to Tha'er Halahlah and Bilal DIab and Jafar Ezzidein and all the other prisoners, Israel should be responsible and bare the consequences and consider that the truce is no longer binding," said al-Batsh.
The Israeli military's detention process also allows for detention based on secret evidence, and there is no requirement to charge the detainees or to allow them to stand trial.
Diab and Halahlah, members of the Gaza-based militant group Islamic Jihad, are both in custody under administrative detention. Diab has been in custody for nine months, while Halahlah has been in custody for 22 months.
On Sunday, Al-Khatib said his clients were nearing death and accused the Israeli high court of procrastinating in delivering a ruling.
"I believe what the court is doing here is trying to break the will of both prisoners so they will back down in their hunger strike," he said.
An Israeli foreign ministry spokesman, Yigal Palmor, told CNN that both men "were arrested for their direct involvement in promoting terror" and suggested that administrative detention constituted "the only available means to thwart the danger" the men posed to Israel.
Amany Daify, a project coordinator for Physicians for Human Rights, an Israeli group advocating on behalf of the hunger striking prisoners, said both prisoners "are in a life-threatening condition" and continued to refuse to be given minerals or liquids.
More than 4,500 Palestinian prisoners are in Israeli prisons for a variety of offenses, ranging from rock-throwing to murder. Of these, about 300 are being held in administrative detention, according to rights groups.
The vast majority of prisoners refusing to eat began their protest April 17, while a handful have been without food for longer.
While hunger strikes are not a new tactic of Palestinian resistance, a series of recent high-profile cases has brought increased attention to the practice and served as a rallying cry for Palestinians, who have staged multiple protests in the West Bank and Gaza in support of prisoners.
Besides the administrative detention policy, the Palestinian detainees' principal demands are an end to solitary confinement, arbitrary night raids and what they term indecent searches of prisoners. They also want access to educational material, improved food and access to television.
They also want family members living in Gaza to be permitted to visit.
A committee representing prisoners must approve any proposed agreement in order for the hunger strike to end.
CNN's Kevin Flower and Guy Azriel contributed to this report.