Turkey warned Russia not to get involved as it retaliated against Syrian government forces for killing four of its soldiers in northwest Syria on Monday.

Militants blew up a gas pipeline Sunday in Egypt's restive Sinai Peninsula, security sources said.

Turkish and Syrian troops traded fire in northwest Syria on Monday, with more than 20 reported dead, further raising tension between Ankara and regime backer Moscow over the war-torn Idlib rebel enclave.

Russian air strikes also killed 14 civilians in the same area, where a government offensive has caused one of the worst displacement waves of the nine-year-old Syrian conflict, a monitoring group said.

Air strikes by the regime and its Russian ally on Sunday killed nine civilians in the last major opposition bastion of Idlib in northwestern Syria, a Britain-based war monitor said.

An Israeli cabinet meeting Sunday during which officials said Prime Minister Benjamin Netanyahu would seek approval to annex parts of the occupied West Bank has been scrapped, his office said.

Authoritarian governments in the Middle East are increasingly willing to seize researchers and academics, who are seen as valuable bargaining chips in their joustings with Western nations, analysts warn.

Israel launched air strikes on the Gaza Strip early Sunday in retaliation for projectiles fired from the Palestinian enclave into southern Israel, the army said.

Furious anti-government youth held their ground in protest squares across Iraq's south on Sunday, despite the previous evening's appointment of a prime minister who insists he is an independent. 

Israeli warplanes hit the Gaza Strip's Islamist rulers Hamas on Saturday after cross-border mortar fire by Palestinian militants, the Israeli army said.

Palestinian leader Mahmud Abbas on Saturday announced a cut in all ties with Israel and the United States, including security cooperation.