RAMALLAH (Ma’an) -- Jailed Fatah leader Marwan Barghouti was sent to solitary confinement on Wednesday after making critical comments about Israel to journalists.

After testifying in a Jerusalem court on Wednesday the Fatah leader briefly spoke to reporters.

Upon returning to Hadarim prison in Israel, Barghouti was not allowed back into his regular cell and was instead put in isolation, the Palestinian Prisoners' Society said Thursday.

Detainees in the prison protested the move and asked prison authorities to explain their decision.

Israeli authorities have not responded.

Barghouti, the former secretary-general of Fatah in the West Bank, told journalists that the Palestinian-Israeli conflict would only be resolved when the occupation comes to an end and Israel withdraws to the pre-1967 borders.

The Palestinian Prisoners' Society condemned the Israeli decision to isolate him and called on human rights organizations to stop violations against Palestinian leaders in jail.

The Fatah leader has been serving a life sentence since 2004 and has been widely viewed as a contender to succeed Mahmoud Abbas as president.