Prisoners are demanding more contact with relatives, better access to medical treatment and an end to the Israeli practice of detention without trial.
Thousands of Palestinians took the streets of the West Bank and the Gaza Strip to mark Prisoners Day on Monday and express their solidarity with hunger-striking prisoners in Israeli prisons.
Convicted Fatah terrorist Marwan Barghouti (center) is escorted by Israeli police into the Jerusalem Magistrate's Court to testify as part of a United States civil lawsuit against the Palestinian leadership, in January 2012.
Reports suggest that he is widely seen as a possible future Palestinian president.
"The number of prisoners taking part in the mass hunger strike is expected to increase but authorities have begun to crackdown on the protest", Issa Qaraqe, the head of the Palestinian Committee of Prisoners Affairs, told The New Arab.
As the strike for better conditions involving more than 1,100 prisoners in eight prisons entered its second day, the Israeli authorities moved swiftly to contain the protest, dispersing key figures to different prisons and ordering searches to prevent inmates sending messages.
Israeli prisons hold around 6,500 Palestinians, including 300 minors.
There are now 6,300 Palestinian political prisoners, 500 of them in administrative detention, according to the Palestinian prisoners' rights group, Addameer.
Others are detained under so-called Administrative Detention, which allows suspects to be held without charge for six-month intervals.
Israel controls the West Bank, East Jerusalem and the Gaza Strip, territories it has seized in the 1967 Middle East war, despite worldwide criticism.
He confirmed that Barghouti was transferred to another jail and was placed in solitary confinement.
"These are terrorists and incarcerated murderers who are getting exactly what the worldwide law requires", he told Israel's Army Radio, adding that under the ministry's policy, "you can't negotiate with prisoners such as these".
It is led by jailed Marwan Barghouti, a leader of the Fatah movement of the Palestine Liberation Organization, who is serving five life terms after being convicted of murder in the killing of Israelis in a 2000-05 uprising.
Israel has denied suggestions that Palestinian prisoners have been left in poor conditions.
Top Palestinian official Hanan Ashrawi called on the worldwide community to bring an end to the "inhumane" treatment of Palestinian prisoners, which she said was in violation of the Geneva Convention. "My policy is that you can't negotiate with prisoners such as these. They were brought to justice and are treated properly under global law". Erdan insisted that there was no need to negotiate at all about their prison system's actions, and that they had no reason to improve conditions for the detainees.