The Knesset (Israel's parliament) approved a preliminary reading of a controversial bill that would allow Israeli authorities to impose the death penalty on Palestinians involved in "operations against Israeli targets."

Israeli military courts – which handle cases involving Palestinians in the occupied West Bank – already have the power to issue the death sentence, although it has never been implemented. The only case of an execution in Israel was carried out against convicted Nazi war criminal Adolf Eichmann in 1962.

The amendment to the penal code would still require three more readings if it is to become law. Currently, a death penalty can only be imposed if a panel of three military judges passes sentence unanimously. If the amendment is adopted, a majority verdict would suffice.

Wednesday's motion was brought by Defense Minister Avigdor Lieberman, an ultra-nationalist in the conservative coalition government, who advocates tough action against Palestinians convicted of attacking Israeli civilians and soldiers. Fifty-two of parliament's 120 members voted in favor, and 49 were opposed.

Last year, Benjamin Netanyahu voiced his support for applying the death penalty to those he described as "terrorists with blood on their hands."

Because of Israel's dual legal system, which generally tries Israelis in civilian courts and Palestinians in military courts (where the death penalty would be introduced), Israelis would generally not face execution.

"The fact that Israel lacks a constitution allows its prime ministers to enact legislation that serves the interests of their respective racist governments," Mohammad Dahleh, a Palestinian expert on Israeli affairs, told Anadolu Agency (AA).

"Israel refuses to adopt a constitution," he said. "This allows it to create laws -- or modify them -- commensurate with its expansionist tendencies."

Yasser al-Amouri, a Palestinian expert on international law, said the new legislation violated basic international legal tenets.

"The conflict between the Palestinians and Israelis is not criminalist in nature but nationalist," he said. "This means Israel can't sentence Palestinian prisoners to death under the provision of the Fourth Geneva Convention relating to the treatment of prisoners of war," he explained.

Issa Qaraqe, the head of the Palestine Liberation Organization's (PLO) committee on detainees, for his part, told Anadolu Agency that the new legislation would allow Israel to "retaliate" against Palestinian prisoners with "legal cover."

"The occupying state of Israel should not apply its laws to the Palestinian people. Palestinian prisoners must be protected in line with international law; they should not be treated as convicted criminals," he said.

Qaraqe urged the international community to intervene on behalf of Palestinian prisoners and pressure Israel to abide by its obligations under international law.

According to official Palestinian figures, roughly 6,400 Palestinians are currently being held in prisons and detention facilities throughout Israel.