The Arab League on Tuesday came under mounting pressure to act after Syria's regime failed to implement its peace blueprint and tightened a bloody siege on the flashpoint city of Homs.
The United Nations said meanwhile that the regime's repression has left more than 3,500 people dead since protests against the autocratic rule of President Bashar al-Assad erupted in mid-March.
And in Brussels, diplomats said the EU is readying a freeze on European Investment Bank credits to Syria as it mulls more sanctions on Assad's regime, with a decision expected at a meeting of foreign ministers next Monday.
The Syrian Observatory for Human Rights said 14 people were killed across the country on Tuesday alone, among them a girl who died in Homs, as soldiers pressed on a military campaign in the central industrial hub.
A civilian was killed during raids in the neighbourhood of Baba Amro," where soldiers were searching for people wanted by the regime's security services, the Britain-based rights group said in a statement.
Ravina Shamdasani, spokeswoman for the UN High Commissioner for Human Rights, described the situation in the embattled neighbourhood as "appalling," with residents deprived of food, water and medical supplies for the past week.
In another neighbourhood of Homs, "a girl was killed by the explosion of a rocket that hit her home," said the Observatory.
And in Qusayr, near Homs, overnight clashes pitted soldiers against gunmen presumed to be defectors.
"Eight gunmen and security agents were killed in an ambush by armed men, probably army defectors," south of Maaret al-Numan, a town in Idlib province near the border with Turkey, it added.
Security forces also killed three civilians in the same province and "five people were wounded" when troops in armoured vehicles opened fire on the highway linking Damascus with the second city of Aleppo.
In a letter, the opposition Syrian National Council urged the Arab League "to take a strong and effective position against the Syrian regime commensurate with the dangerous development of the situation in Syria, especially in... Homs."
It wants the League to freeze Syria's membership, impose economic and diplomatic sanctions, and seek the referral of allegations of genocide and other human rights violations by the regime to the International Criminal Court.
British Foreign Secretary William Hague joined the chorus demanding the Arab League respond promptly to Syria's failure to abide by its commitments.
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"I call on the Arab League to respond swiftly and decisively to the Syrian regime's failure to implement the agreement so far," said Hague. "The international community looks to these Arab nations to show decisive leadership to address this crisis in their midst."
Hague urged the regime to end the siege of Homs and "allow in international and relief efforts (and) to withdraw all Syrian forces from the towns and cities of Syria in accordance with its agreement with the Arab League."
The Syrian National Council, which groups the main opposition currents, has declared Homs a "humanitarian disaster area" in need of "international protection of civilians."
Homs is the only major city to remain outside the Assad regime's control after deadly assaults in Hama further north, Deir Ezzor in the east and the coastal cities of Latakia and Banias.
The United Nations said Syrian security forces have killed 60 people since Assad's regime signed up to the Arab League peace agreement on Wednesday last week.
Shamdasani of the UN High Commissioner for Human Rights said that, nationwide, "the brutal crackdown on the dissent in Syria has so far claimed the lives of more than 3,500 Syrians."
"There was a peace plan by the league of Arab states that the Syrian government had engaged to, but since the peace plan was signed, there have been further killings, further sieges of towns and really shocking reports coming out from the ground," she noted.
With NATO ruling out operations and UN Security Council sanctions unlikely because veto-holders Russia and China are allies of Assad's regime, regional actors have come to represent the best avenue to pressure Damascus.
The Arab roadmap called for an end to violence, the release of those detained, the withdrawal of the army from urban areas and free movement for observers and the media, as well as talks between the regime and opposition.
As a first step, Syria said Saturday it had released more than 550 people who were arrested during anti-regime protests, to mark the Eid al-Adha Muslim feast.
However Shamdasani said at least 19 people were killed on Sunday, first day of the Eid.
And she noted that despite the prisoner release, "tens of thousands continue to remain in detention and dozens continue to be arbitrarily arrested every day."
The Cairo-based Arab League has called an emergency meeting on Saturday to address the crisis in Syria.