President Barack Obama's top foreign policy adviser Susan Rice on Friday said Washington was providing "lethal and non-lethal" support to select members of the Syrian opposition, offering more detail than usual on U.S. assistance.

Top Obama administration officials typically decline to say exactly what equipment, arms or ammunition the United States is providing to moderate Syrian opposition forces.

Guided more by what they can hear than see, Syrian troops and rebels are battling in the bowels of Damascus, digging tunnels in a campaign to control the eastern entrance to the capital.

This is the suburb of Jobar, next to Abassid Square, a stronghold of President Bashar Assad's regime. The army knows that if it is lost to the rebels, the capital's entire defenses are in danger.

Twin suicide bombings targeting Iraq's Shabak minority and fighting between security forces and militants killed 33 people in the northern province of Nineveh on Friday, officials said.

Provincial capital Mosul is one of Iraq's most dangerous cities, with well-entrenched militant groups carrying out almost daily attacks.

The Italian navy on Friday said it had rescued around 2,500 asylum-seekers from 17 boats in the past 24 hours as good weather conditions in the Mediterranean further boost the influx of asylum-seekers trying to reach Europe.

The navy said in a statement that the San Giorgio, an amphibious transport dock ship, had picked up the highest number -- 998 migrants including 214 women and 157 minors.

The shadowy leader of thousands of Islamist fighters in Syria and Iraq, many of them Westerners, appears to be surpassing al-Qaida chief Ayman al-Zawahiri as the world's most influential jihadist.

Abu Bakr al-Baghdadi's Islamic State of Iraq and the Levant -- known for its ruthless tactics and suicide bombers -- is arguably the most capable force fighting Syrian President Bashar Assad, and has even held control of a major Iraqi city for the past five months, in tandem with other groups.

Progressive Socialist Party leader MP Walid Jumblat criticized on Thursday the Syrian presidential elections with a caustic and sarcastic statement, noting the regime's bloody crackdown against the people and the international community's disappointing stances towards the Syrian people.

He said sarcastically: “The regime could have achieved better results in the glittering, diverse, transparent, and democratic elections, had the dead, which exceeded 200,000, and displaced, who exceed eight million, been able to cast their votes.”

Al-Mustaqbal movement leader MP Saad Hariri on Thursday called for “real global solidarity” with the Syrian people aimed at “eradicating” Syrian President Bashar Assad from political existence.

“No elections in the history of humanity have been deplored and described with degrading terms such as the elections that granted Bashar Assad a new presidential term,” Hariri said in a communique.

Syria's exiled opposition vowed Thursday to continue its uprising against President Bashar Assad, saying his election to a new seven-year term was "illegal".

"The Syrian National Coalition reaffirms that this election is illegal and does not represent the Syrian people," it said in response to Assad's landslide victory in a Tuesday election held only in government-controlled areas.

China offered $16 million in humanitarian assistance Thursday for Syrian refugees in Lebanon and Jordan as part of Beijing's growing engagement with the Arab world.

The assistance will go to displaced Syrians sheltering in neighboring countries, including Jordan and Lebanon, President Xi Jinping was quoted as saying by the official Xinhua News Agency.

The International Committee of the Red Cross has delivered medical supplies to Iraq's Fallujah for the first time since January, it said Thursday, describing the situation in the conflict-hit city as "extremely dire".

A five-member ICRC team visited the city, which has been outside of government control since the beginning of the year, and delivered the supplies to the city's main hospital, which it said would be used to treat patients suffering from burns or other injuries.