Syria's government wants to destroy the UN-brokered peace plan aimed at ending violence in the country, opposition
leader Burhan Ghalioun has said, a day after the deadliest bomb attacks of Syria's 14-month uprising in the capital city.
The blast in Damascus,which the government said left at least 55 people killed and nearly 400 others wounded, did not deter UN monitors from resuming their monitoring mission on Friday.
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Some of the observers were touring Damascus while others planned to visit the suburb of Douma, east of the capital to monitor a 12 April ceasefire brokered by special envoy Kofi Annan.
Ghallioun, the head of the Syrian National Council (SNC), said: "The regime is now trying to kill this Annan plan, and by a new technique which is terrorism."
Ghalioun accused Assad's government of complicity with al-Qaeda over the bombings, alleging that Damascus had liaised with al-Qaeda against US forces in Iraq.
"The regime has operated very closely with al-Qaeda," he told reporters on Friday, adding that the bombings marked a change in tactics.
Leon Panetta, the US defence secretary, suggested on Thursday that al-Qaeda might be taking advantage of instability in Syria and said US intelligence suggested the group was present in the country.
Security Council condemnation
Russia and China, which have stymied Western efforts to heap stronger condemnation on Assad's government, joined a UN Security Council condemnation of the attacks.
The council called on all sides to "immediately and comprehensively" implement the six-point peace plan of UN-Arab League envoy Annan, "in particular to cease all armed violence".
But Ghalioun said the Annan plan was toothless and too easy to ignore.
"If the regime fails to implement the plan, it will not get punished, and that is our concern. Assad feels that he can run away from the plan without any consequences."
Ghalioun was speaking in Tokyo where he is attempting to rally diplomatic support for his opposition movement.
The Syrian government and opposition traded the blame for the twin bomb attacks in Damascus
Assad's traditional allies, Russia and China, continue to block substantial moves by the international community to pressure Assad's government.
Despite the violence, activists planned fresh anti-government protests across the country on Friday.
The Syrian Observatory for Human Rights, a London-based rights group, has said that almost 12,000 people, mostly civilians, have been killed in Syria since the revolt, inspired by Arab Spring uprisings, broke out in March last year.
About 800 of them have died since a UN-backed truce was supposed to have taken effect.
Damascus was hit by two blasts on May 6, with three soldiers wounded in one of the attacks. Television footage showed a mangled car destroyed by one of the explosions.
A deadly suicide bombing at Zein al-Abidin mosque in Damascus' central Midan district on April 27 killed 11 people and wounded dozens, according to state media.
An armed group calling itself Al-Nusra Front had earlier claimed responsibility for a deadly suicide bombing on April 20 near the Syrian city of Hama that targeted a restaurant used by the security forces.
The Syrian authorities regularly blame the blasts on what it calls "terrorist groups".
Source: Al Jazeera and agencies