Syrian rebels bomb security building in Damascus BEIRUT (Reuters) - Syrian insurgents detonated bombs at a building occupied by pro-government militias in Damascus on Tuesday and France called for U.N. protection of rebel-held areas to help end Syria's bloodshed and rights abuses. Activists say that more than 27,000 people have been killed in the 18-month-old uprising against President Bashar al-Assad but jostling for regional advantage by world powers has thwarted effective U.N. Security Council action to defuse the conflict. The United States, European allies, Turkey and Gulf Arab states have sided with the Syrian opposition while Iran, Russia and China have backed Assad, whose family and minority Alawite sect have dominated the major Arab state for 42 years. With no foreseeable prospect of foreign intervention and peace diplomacy stuck, outgunned rebels have relied increasingly on attacks with home-made bombs, striving to level the playing field against a state using fighter jets, artillery and tanks. Rebels said they hoped their attack would kill top-level security officials - as they did with a major Damascus bombing in July - but gave no casualty figure. At the annual U.N. General Assembly in New York, French President Francois Hollande sought to shake up international inertia over Syria's crisis by demanding credible U.N. protection of areas now in insurgent hands. "The Syrian regime ... has no future among us," Hollande said in a speech. Without any delay, I call upon the United Nations to provide immediately to the Syrian people all the support it asks of us and to protect liberated zones. Protection for "liberated" areas would require no-fly zones enforced by foreign aircraft, which could stop deadly air raids by Assad's forces on populated areas. But there is little chance of securing a Security Council mandate for such action given the continuing opposition of veto-wielding members Russia and China. How long can we accept the paralysis at the U.N.? Hollande said from the U.N. podium. France in August started funneling aid to rebel-held parts of Syria so that they could administer themselves and help staunch an outflow of refugees. But Western powers have shied from supplying military aid to the rebels to an extent that could turn the tide of the conflict, in part out of fear of arming Islamist militants who have joined the anti-Assad revolt. In another speech to the General Assembly, Qatari Emir Sheikh Hamad bin Khalifa al-Thani said Arab nations should intervene in Syria given the Security Council's failure to stop the civil war. Qatar, which backs the rebels, earlier called on big powers to prepare a "Plan B" within weeks and set up a no-fly zone to provide a safe haven inside Syria in case international mediator Lakhdar Brahimi fails to make headway. The Qatari emir said he believed Arab and European countries would be ready to take part, despite their public wariness of committing the forces needed for such a mission. Addressing the General Assembly, U.S. President Barack Obama accused Iran of helping keep a dictatorship in power in Syria. Syria's conflict, once a peaceful protest movement, has evolved into a civil war that the U.N. special envoy to Syria, Lakhdar Brahimi, said was "extremely bad and getting worse."