Syrian National Council leader Burhan Ghalioun said Friday that Hizbullah chief Sayyed Hassan Nasrallah’s recent remarks that the Syrian opposition had presented its credentials to the West were “inappropriate coming from the leader of a resistance movement and a spiritual figure.”

In an interview on Al-Arabiya television, Ghalioun added: “Neighboring Lebanon is a real brother of Syria and it is more than a neighbor.”

Hizbullah on Friday accused the United States of being behind a bombing in Damascus which official Syrian media said killed 25 people and wounded dozens more, describing Washington as a "terrorist."

"This terrorist crime targeting the heart of the Syrian capital is the second installment of a plan by the evil force, the United States, to punish Syria for standing by the Resistance against the Zionist enemy," a statement by the group said.

Former prime minister Saad Hariri on Friday denied what he said was a “rumor” of a failed attempt on his life in the Saudi capital Riyadh.

“You might have heard the rumor about my so-called assassination in Riyadh. My presence here, now, is a natural denial of this lie,” Hariri said in English on the social networking website Twitter.

Syrian activists on Friday took to the streets across the country in a bid to "internationalize" their cause after the rebel Free Syrian Army urged the Arab League to admit its observer mission is a failure and to turn to the United Nations.

But there has been no let-up in security force fire against demonstrators, with at least 35 people shot dead on Friday, according to the Local Coordination Committees, the main activist group spurring protests on the ground.

The Arab League mission sent to monitor unrest in Syria is unable to do its job properly, French Foreign Minister Alain Juppe said Friday.

"We support the Arab League which has sent observers to Syria but this mission is not at present able to do its job properly," Juppe said on the second day of a visit to Tunisia.

A suicide bombing hit Damascus on Friday, killing 25 and wounding dozens of mostly civilians, state media said, blaming "terrorists" for the second such attack on the Syrian capital in two weeks.

But Syria's opposition Muslim Brotherhood called for an international and Arab probe into the bombing, saying it was an act benefitting the regime.

U.N. human rights experts may train Arab League observers monitoring the Syrian government's deadly crackdown on opposition protests, a U.N. spokesman said Thursday.

The announcement came the day after Qatar's prime minister sought help from U.N. secretary general Ban Ki-moon, saying the Arab League mission in Syria had made "some mistakes".

Two leading Syrian opposition groups voiced their desire Thursday to resolve a rift and unite against President Bashar al-Assad's regime, Belgium's foreign minister said after talks with the two.

Saying divisions were "playing in the hands of the Syrian regime," Belgian Foreign Minister Didier Reynders called for a "unified opposition platform," his office said in a statement.

The head of the Free Syrian Army demanded Thursday that the Arab League pull its observer mission out of the country over its failure to halt almost 10 months of bloodshed.

Colonel Riyadh al-Asaad issued the call in an interview with AFP after the Arab League turned to the United Nations for help and admitted "mistakes" in the monitoring mission launched less than two weeks ago.

Syria on Thursday released 552 people who were detained over their involvement in political unrest and who have "no blood on their hands," the official SANA news agency reported.

The news agency said that "552 prisoners involved in the latest events in Syria and who have no blood on their hands were released."