Israel's parliament has passed a law that could block the release in any future peace negotiations of Palestinian prisoners convicted of murder, a spokesman said Tuesday.

The 120-member Knesset voted late Monday 35 to 15 in favor of the bill, which was initiated by a far-right politician and approved by the cabinet in June, a parliament spokesman told Agence France Presse.

Israeli plans for roughly 500 new settler homes in occupied east Jerusalem are a "slap in the face" of the United States and the international community, a top Palestinian official said.

Israel approved construction of the homes on Monday as chief Palestinian negotiator Saeb Erakat met U.S. Secretary of State John Kerry in the United States, according to settlements watchdog Peace Now.

Israel approved Monday plans for some 500 new settler homes in occupied east Jerusalem, a watchdog said, a week after a government pledge to build the structures drew Palestinian ire.

The interior ministry gave the go-ahead for the units located in the existing settlement of Ramat Shlomo in volatile east Jerusalem, the Peace Now non-governmental organization told AFP.

An Arab Israeli citizen on Monday was sentenced to 22 months in prison for joining the Islamic State jihadist group in Syria, Israeli court documents showed.

Ahmed Shorabji, a 23-year-old resident of the northern town of Umm al-Fahm, traveled to Syria on January 16 "illegally with several others and with the help of people smugglers" via Turkey, according to the verdict, seen by AFP.

Israeli police arrested at least 23 Palestinians in east Jerusalem overnight and during Monday, Palestinian officials said, in the latest crackdown after months of violent clashes in the Holy City.

But a police spokeswoman confirmed only four arrests, without accounting for the number of people who might have been arrested by other security services.

Palestinian President Mahmud Abbas has outraged Israeli leaders by calling the attempted assassin of a Jewish ultra-right-wing rabbi a "martyr" and the soldiers who killed him "terrorist gangs".

Abbas on Sunday sent a letter of condolence to the family of 32-year-old Muataz Hijazi, killed by Israeli police who said he had tried to murder Yehuda Glick.

The Israeli cabinet approved a new law Sunday that would enable easier conversions to Judaism, a move advocates hope will encourage hundreds of thousands of "religionless" Israelis to become Jewish.

The new law, a ministerial compromise following a bill initiated by Elazar Stern of Justice Minister Tzipi Livni's HaTnuah movement, stipulates that the chief rabbi of each Israeli city would be able to form and head a conversion court, pending conditions to be set by the chief rabbinate.

The incoming head of Israel's Northern Command, Maj.-Gen. Aviv Kochavi, has warned that terrorist groups could join Hizbullah and Iran in carrying out attacks on the Jewish State.

“The radical axis of Iran, Syria and Hizbullah, which operated for many years to harm the state of Israel, may be joined by the threat of terror organizations that possess an extremist ideology and can change their goals and begin targeting the state of Israel,” Kochavi said on Sunday.

The Arab League warned Sunday that Israel has reached a "red line" after fresh clashes in Jerusalem, urging international pressure to stop what it branded "violations" in the holy city.

Clashes around the flashpoint al-Aqsa mosque compound -- the third holiest site in Islam and Judaism's holiest -- prompted Israel on Thursday to close the site for a day.

An Israeli far-right lawmaker visited the Al-Aqsa mosque compound in east Jerusalem on Sunday, pressing for Jews to be allowed to pray there despite heightened tensions over its status.

In renewed clashes with Israeli police on Saturday night around east Jerusalem, 17 Palestinian protesters were detained, police spokeswoman Luba Samri said, raising to 111 the number arrested in protests since October 22.