Israeli forces are carrying out more special operations beyond the country's borders and will be ready to attack Iran's nuclear sites if ordered, the chief-of-staff said in an interview on Sunday.

In an extract from an interview with the top-selling Yediot Aharanot daily, Lieutenant General Benny Gantz said that 2012 would be a critical year in efforts to halt what Israel and much of the international community believe is an Iranian nuclear arms program.

At least 1,350 Palestinian prisoners being held in Israeli jails are observing an open-ended hunger strike, the Israeli Prisons Service said on Sunday, after another 150 inmates began refusing food.

"There are now 1,350 Palestinian prisoners on hunger strike," said Sivan Weizman, spokeswoman for the Israel Prisons Service (IPS).

Israeli Prime Minister Benjamin Netanyahu sought to sidestep strife in his right-wing coalition on Sunday by forming a committee to seek legal solutions to contested settlement projects.

The dispute centers on the government's policy on settlements in the occupied West Bank and its commitment to dismantle a number of unauthorized settler outposts in line with a supreme court ruling of August 2011.

An Israeli court has ordered a group of Jewish settlers to leave a house in the southern West Bank city of Hebron after ruling that their claim to ownership was false, court documents showed.

In a hearing at Jerusalem District Court, Judge Ram Winograd ruled late last week that the settlers' argument that they had legally purchased the property, "does not hold water."

U.N. envoy Kofi Annan on Sunday asked the Damascus regime and the opposition to immediately halt violence and the use of heavy weapons.

"I urge all forces whether governmental, opposition or others to put down their weapons and work with the United Nations monitors to consolidate the fragile cessation of violence in all its forms," Annan said in a statement.

A French man working for the International Committee of Red Cross (ICRC) was kidnapped in Yemen Saturday on his way to the port city of Hudaida, an ICRC spokeswoman told AFP Sunday.

"We haven't had any contact with his captors. We are very concerned for his health and well-being," spokeswoman Marie-Servane Desjonqueres said, adding "We are hoping for his immediate and unconditional release."

Two U.N. observers set up base Sunday in the restive city of Homs a day after an advance team of monitors toured flashpoint areas to assess a shaky truce, a mission spokesman told AFP.

The official, Neeraj Singh, also said other members of the eight-member U.N. team of advance observers mandated to monitor the April 12 ceasefire were pursuing field visits elsewhere in Syria on Sunday.

Seventeen suspected Al-Qaida militants were killed in an air raid that struck one of their hideouts in the southern town of Loder, the defense ministry said on Sunday.

The late Sunday attack brought to 57 the number of Islamist insurgents reportedly killed in south Yemen over the past three days, according to the defense ministry. Agence France Presse could not independently verify the toll.

Iraqi Prime Minister Nouri al-Maliki arrived in Tehran on Sunday for two days of meetings with Iranian leaders and senior officials on various bilateral issues, Iran's IRNA state news agency reported.

The visit notably comes ahead of an important May 23 meeting to be hosted in Baghdad between Iran and the P5+1 group of world powers on Tehran's disputed nuclear program.

The rebel Free Syrian Army hailed the United Nations Security Council vote on Saturday to send 300 observers to monitor a ceasefire in Syria and said it was committed to the truce.

"We salute the dispatch of new observers," FSA spokesman Colonel Kassem Saadeddine told Agencce France Presse through a Skype call from Homs province.