Yemeni troops launched an all-out offensive on Saturday to retake the southern city of Zinjibar, held for a year by al-Qaida gunmen, in fighting that killed 12 people, military and local sources said.

The "wide offensive" began from three sides and is supported by the air force and the navy," said a military official, adding that Defense Minister Mohammed Nasser Ahmed is supervising the operation from nearby.

Egypt's administrative court on Saturday ruled that this month's presidential election should be held on time, overturning a lower court's ruling, judicial sources said.

A provincial administrative court had ordered the suspension of the election on Wednesday, saying the electoral commission chief had overstepped his mandate by calling for the May 23 and 24 vote.

Gulf leaders will discuss a proposal for a closer political union among them that could begin with Saudi Arabia and Bahrain, the Bahraini information minister said on Saturday.

"The idea of a Gulf union will be on the agenda of the summit in Riyadh" on Monday, said Samira Rajab.

Algeria's polls were a step towards reform, European Union observers said Saturday, listing a number of shortcomings in the process but stopping short of challenging its overall credibility.

Official results for Thursday's legislative election yielded a higher than expected turnout of 42 percent and tightened the ruling party's grip on power, bucking the Arab Spring of regime change and Islamist breakthroughs.

Al-Nusra Front, an Islamist group unknown before the Syrian revolt, released a video on Saturday claiming responsibility for twin suicide bombings in Damascus that killed 55 people.

The video says the Thursday bombings, the deadliest since the uprising against President Bashar Assad's regime erupted in March 2011, were "in response to regime bombing of residential areas in Damascus, Idlib, Hama, Daraa provinces and others."

Violence in Syria cost at least 10 lives on Saturday as a U.N force to oversee a truce neared half its planned .strength, monitors said.

In Idlib province, a stronghold near the Turkish border of rebels fighting President Bahar Assad's regime, security force gunfire killed a man and a woman during a series of raids, the Syrian Observatory for Human Rights said.

Israeli and Egyptian officials are making progress in attempts to end a mass hunger strike by Palestinian prisoners, some of them close to death, Gaza's Hamas prime minister said on Saturday.

"There was progress in talks between Egypt and Israel," Ismail Hanieh said in a statement. "This is an important development concerning the demands of the prisoners."

Two Turkish journalists who were detained for two months in Syria are on their way home following mediation by Iran, Turkish Foreign Minister Ahmet Davutoglu announced Saturday.

"I have just spoken with Iranian Foreign Minister (Ali Akbar) Salehi. Our two journalists, Adem Ozkose and Hamit Coskun, about whom we had no news since they left for Syria, are on their way to Tehran now," Davutoglu said on Twitter.

The United States said Friday it was partially resuming sales of military supplies to Gulf Arab ally Bahrain after having frozen most shipments last year amid a bloody crackdown on protests.

But in a nod to concerns over ongoing pro-democracy demonstrations, State Department spokeswoman Victoria Nuland said "the items that we are releasing are not used for crowd control."

Algeria's Islamists were reeling Saturday from a stinging setback in legislative polls which saw the ruling party come out on top, resisting the Arab Spring's tide of democratic change.

The regime argued that the results showed Algerians' desire for stability, at a time when regime change was bringing chaos to other countries, and outright rejection of Islamism, whose rise 20 years ago led to civil war.