China's Foreign Minister Yang Jiechi urged a visiting Syrian envoy on Thursday to implement a ceasefire and accept international mediation to end the violence wracking the country.

"China urges the Syrian government and all concerned parties... to quickly implement a ceasefire to end the violence and start political dialogue," Yang told Bouthaina Shaaban, according to a government statement.

Israel is an artificial "outgrowth" in the Middle East that "will disappear," Iran's supreme leader, Ayatollah Ali Khamenei, said ahead of rallies on Friday against the Jewish state and supporting the Palestinians.

The annual Quds Day marches were started in 1979 after the founding of the Islamic republic. The protests use the word Quds, derived from Arabic, to designate the city of Jerusalem.

French Foreign Minister Laurent Fabius said on Thursday Syrian President Bashar Assad was "butchering his own people" and that the sooner he leaves the better.

"France's position is clear: we consider Assad to be butchering his own people. He must leave, and the sooner he goes the better," Fabius told reporters at the Zaatari refugee camp, which houses around 6,000 Syrians in northern Jordan.

The Syrian army pummeled districts across the embattled northern city of Aleppo on Thursday, leaving 18 civilians dead, while eight soldiers died in clashes with rebels, a watchdog said.

The violence, which nationwide left 34 dead so far on Thursday, followed a bloody day in which at least 172 people were killed across Syria including in an air strike in the northern town of Aazaz, the Syrian Observatory for Human Rights said.

Iran on Thursday slammed a decision by the Organization of Islamic Cooperation to suspend Syria's membership, calling the step against its key ally "unfair and unjust."

"Syria should have been invited to the summit to defend itself," Iran's foreign minister Ali Akbar Salehi told the official IRNA news agency in the holy Muslim city of Mecca.

Turkish warplanes bombed areas of north Iraq in a bid to target rear bases of the Kurdistan Workers' Party (PKK) overnight into Thursday, a spokesman for the rebel group said.

"Turkish warplanes struck around midnight against several areas in the Kurdish Iraqi area," Haval Roz told Agence France Presse.

A wave of attacks across Iraq on Thursday killed at least 19 people, as an analyst warned of a potential escalation in violence to coincide with the end of the Muslim fasting month of Ramadan.

Officials reported more than 100 people were wounded in 15 explosions, including seven car bombs, a suicide attack, and a shooting, in nine cities and towns nationwide, a day after attacks left 13 people dead.

U.N. aid chief Valerie Amos said Thursday she was still pushing Damascus to allow international aid organizations to operate in Syria, warning that more than one million Syrians faced "destitution.”

"Over a million people have been uprooted and face destitution. Perhaps a million more have urgent humanitarian needs due to the widening impact of the crisis on the economy and people's livelihoods," she told reporters in Damascus.

About 15 Syrians have died in Turkish hospitals of their wounds from an air strike after 100 were sent across the border for treatment following the attack, a Turkish official said Thursday.

Many of those injured suffered severe burns in Wednesday's air strike by a Syrian air force MiG fighter jet in the town of Aazaz near Aleppo, which killed more than 30 people instantly and left more than 200 injured.

Israel on Thursday wound up nationwide testing of an SMS warning system against missile attack, sending texts to mobile phones in Jerusalem and other parts of the country, a military spokeswoman said.

The five-day exercise, which began on Sunday, took place to the backdrop of mounting speculation over a possible Israeli strike on Iran's nuclear facilities and a resulting Iranian counter-attack.