The Arab League chief described the situation in Syria as amounting to war crimes and said those responsible will be held accountable internationally, Egypt's state news agency said on Sunday.
Rebels still in control of sections of Aleppo, Syria's largest city, have clashed for several days with army troops after additional tank columns and troop reinforcements were sent in last week.
"Dr. Nabil Elaraby, Secretary-General of the Arab League, described what is happening in Syria, especially the city of Aleppo, as amounting to war crimes, and warned that perpetrators of these crimes will be held internationally accountable," state news agency MENA said.
Meanwhile, Saudi Arabia said Syrians should be enabled to protect themselves against government attacks but declined direct comment on a report that it had helped set up a secret liaison centre in Turkey to aid a rebellion against President Bashar Assad.
Gulf sources told Reuters on Friday that Saudi Arabia, Turkey and Qatar had established a centre in Adana, southeastern Turkey, to help the rebel Free Syrian Army with communications and weaponry as it battles in major cities against forces loyal to Assad.
"The very well-known position of the kingdom of Saudi Arabia is to extend to the Syrian people financial and humanitarian assistance, as well as calling upon the international community to enable them to protect themselves at the very least if the international community is not able to do so," a foreign ministry spokesman said by text message on Saturday, answering a Reuters query about the base.
"The Syrian regime is importing and using all kinds of weapons to fight and oppress its own people in a fierce war as if it's launched towards a foreign enemy - not against its disarmed population", the spokesman added.
The Gulf sources had also said the Adana centre, which is near the Syrian border and a U.S. airforce base at Incirlik, was set up at the suggestion of Saudi Deputy Foreign Minister Prince Abdulaziz bin Abdullah during a trip to Turkey.
However, the foreign ministry spokesman said Prince Abdulaziz, who was promoted to deputy foreign minister last year, and is a son of King Abdullah, had not visited Turkey.
Saudi Arabia, the largest Gulf Arab country by size and population has led efforts by Sunni Muslim states to isolate President Assad's government, which is dominated by members of the Alawi Shi'ite sect, since the outbreak of a popular revolt against him early last year.
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