By Sami Aboudi
DUBAI, June 14 (Reuters) - A senior cleric in Islam's holy city Mecca exhorted followers on Friday to support Syrian rebels by "all means", the latest in a series of rhetorical attacks on President Bashar al-Assad reflecting rising sectarian tension across the Middle East.
His appeal came at a time when momentum on the battlefield has been shifting in Assad's favour, just a few months after analysts wrote him off, making the prospect of his swift removal and an end to Syria's civil war look remote in the near future.
The Sunni Muslim-led revolt against Iranian-backed Assad, whose Alawite minority is a branch of Shi'ite Islam, has taken on sectarian overtones since the open intervention last month of Lebanon's Shi'ite Hezbollah guerrillas on Assad's side.
In a sermon to worshippers at Saudi Arabia's Grand Mosque in Mecca, Sunni Sheikh Saoud al-Shuraym denounced Assad as a tyrant whose troops he said had raped women, killed children and destroyed homes over the past two years.
"All of that puts on the shoulder of each one of us a share of responsibility before God, on leaders, rulers, scholars, reformers, thinkers and people to take a unified and conscious stand against the mad (crackdown) on our brothers in Syria," Shuraym said in a sermon broadcast on Saudi state television.
"By God..., our brothers need more efforts and determination to be exerted to remove the merciless injustice and aggression through all means and with no exceptions," he told followers. "We tell our brothers in the Levant to be patient."
Saudi Arabia, the Sunni-ruled birthplace of Islam and a pivotal regional ally of the United States against Iran, has been a major financial patron of rebels fighting to oust Assad.
After crack Hezbollah fighters helped Assad's forces retake the border town of Qusair this month from rebels, the influential Qatar-based Sunni cleric Youssef al-Qaradawi announced he had stopped advocating Sunni-Shi'ite reconciliation and was now calling for jihad (Muslim holy war) in Syria.
His call was endorsed by a congress of leading Sunni clerics who met in Cairo on Thursday to discuss the situation in Syria.
Qaradawi's International Association of Muslim Scholars called for a "day of rage" in support of Syria on Friday. But there were no signs of any gatherings around the Gulf region, where street protests are generally banned in most countries.
Shuraym's comments contrasted with the normally apolitical stance taken in sermons by Saudi preachers, who usually reflect the government line in their public utterances.
Last week, for example, Saudi preachers focused on social issues, limiting references to Syria to the usual appeals to God to help those suffering in dire conditions.
In his sermon on Friday, Shuraym did not specify what help Muslims should extend to Syrians. But the kingdom has previously called for providing the outgunned rebels with weapons.
Riyadh, the world's top oil exporter, has been campaigning for international arming of the Syrian rebels, fearing a victory by Assad in the civil war will increase Iranian influence in the Levantine region.
(Reporting by Sami Aboudi and Sylvia Westall, Editing by William Maclean and Mark Heinrich)