Shelling of the Yarmuk Palestinian refugee camp in the Syrian capital killed at least 15 civilians, including two children, the Syrian Observatory for Human Rights said on Friday.

The watchdog said the mortar shells slammed into the camp, on the southern outskirts of Damascus, on Thursday night, as President Bashar Assad's regime pressed its bid to crush an uprising that erupted almost 17 months ago.

The General Security Department’s deportation of 14 Syrians torpedoed efforts to release 11 Lebanese Shiite pilgrims kidnapped in Syria since May, An Nahar daily reported on Friday.

The Lebanese mediator involved in negotiations to set the men free was informed that the talks reached a dead-end following major progress made to secure the safe return of the pilgrims, the newspaper said.

The only way to end the violence gripping Syria is by "political dialogue", a top Syrian politician said in an interview published Thursday.

"The only way out is by political dialogue -- with no preconditions," Minister for National Reconciliation Ali Haidar told the Swiss newspaper Tages-Anzeiger.

European Union foreign affairs chief Catherine Ashton called Thursday for a rapid appointment by the U.N. and the Arab League of a successor to Kofi Annan after he quit as Syria peace envoy.

Expressing her "deep regret" in a statement, the English baroness said the EU "calls for the early appointment of a successor to carry on Mr. Annan's work towards a peaceful political transition in Syria."

U.S. President Barack Obama on Thursday approved an extra $12 million in U.S. lifesaving humanitarian aid to Syrians to mitigate what he said were President Bashar Assad's "horrific atrocities."

The grant brings to $76 million the total amount of food, water, medical supplies, clothing, hygiene kits and other aid to some of the 1.5 million people in need in Syria, the White House said in a statement.

Former U.N. chief Kofi Annan said on Thursday he was stepping down as international envoy for Syria, complaining that his April peace plan had not received the support it deserved.

As the Syrian army deployed fighter jets against rebels armed with tanks around the commercial capital Aleppo, Annan regretted an "increasing militarization" of the 17-month conflict.

Nearly a third of small- and medium-sized enterprises in Syria have closed since an anti-government uprising erupted in March last year, a business leader said in comments published on Thursday.

"Today, unemployment is rising, and 30 percent of small and medium-sized businesses have closed their doors," Damascus Chamber of Commerce member Sonia Khanji told the pro-government Al-Watan newspaper.

Turkey's military on Thursday staged a military drill on its southeastern border near Syria, just a day after a tank exercise in another border region, the Anatolia news agency reported.

The military tested the speed and maneuverability of the tanks, armored personnel carriers and missile launching platforms deployed in the Mursitpinar region of Sanliurfa province, along the Turkish frontier, said Anatolia.

Australia on Thursday urged the world "not to neglect" the conflict in Syria, where thousands have been killed and many more have fled to neighboring countries.

"We urge the world not to neglect this crisis even for a moment," Australian Foreign Minister Bob Carr told a joint news conference with his Jordanian counterpart Nasser Judeh in Amman.

Progressive Socialist Party leader MP Walid Jumblat accused on Thursday General Security chief Maj. Gen. Abbas Ibrahim of utterly following the Syrian regime’s orders by deporting 14 Syrians.

“It would be useful to remind (Ibrahim) that Syria and during the stability period in the country didn’t have any true concept of independent judicial system, like all the other dictatorial regimes,” Jumblat said in a statement.