Saudi Arabia's execution of a leading cleric from the Shi'ite Muslim minority drew warnings of a backlash against the ruling Al Saud family and threatened to further intensify a wave of sectarian conflict in the region.
Lebanon's Supreme Islamic Shi'ite Council called the execution of cleric Nimr Al Nimr a "grave mistake", and the Hezbollah group termed it an assassination. Ayatollah Ahmad Khatami, an establishment cleric in largely Shia rival Iran, said repercussions against the Sunni Saudi rulers would "wipe them from the pages of history".
Saudi Arabia executed 47 people including Nimr, whom the government accused of inciting violence against the police. His supporters say he is a peaceful dissident who called for greater rights for the kingdom's Shi'ite minority.
Scores of Shi'ites in Saudi Arabia's Eastern Province marched through Nimr's home district of Qatif shouting "down with the Al Saud", and dozens more gathered in nearby Bahrain, a Sunni-ruled island kingdom allied to Saudi Arabia.
In Iran, a Shi'ite theocracy and rival to Saudi Arabia, state media channels carried non-stop coverage of clerics and secular officials eulogising Nimr and predicting the downfall of Saudi Arabia's Sunni ruling family.
Shi'ite leaders in Iraq, Kuwait, Lebanon, and Yemen also warned of reprisals, in a signal that sectarian conflicts across the Middle East could be further inflamed.
On a day where a Saudi-led coalition announced the end of a ceasefire in its war with Yemen's Houthi movement, the Houthis said Nimr had been afforded only a "mock trial".
Three other Shi'ites were executed alongside Nimr, but most of the convicts were jihadists linked to Al Qaeda, a radical Sunni group that regards Shi'ites as heretics and has often targeted them in its attacks.
Shi'ite groups across the region accused Saudi Arabia of using terrorism as a pretext to execute Nimr, a figurehead for the kingdom's restive Shi'ite population who calls for peaceful protests in sermons broadcast online.
The Saudi government says Nimr ordered his followers to attack the police, and was to blame for a series of shooting and petrol bomb attacks that killed several policemen during anti-government protests in Qatif in 2011-13.
"The Saudi government supports terrorists and takfiri (radical Sunni) extremists, while executing and suppressing critics inside the country," Iran's Foreign Ministry spokesman Hossein Jaber Ansari said.
The wave of condemnation could harm Saudi Arabia's efforts to form an Islamic alliance against the jihadist militants of ISIL. Riyadh announced the coalition last month, but did not include the Shi'ite powers.
Lawmakers in Shi'ite-majority Iraq called on the government to sever ties with neighbouring Saudi Arabia, just one day after the kingdom reopened its embassy in Baghdad for the first time since 1990.
Former prime minister Nuri Al Maliki said Nimr's execution would "topple the Saudi regime", while one lawmaker said it had helped ISIL's cause.
Iran's foreign ministry had said on Monday it was willing to talk to Saudi Arabia after months of escalating tensions, but any chance of a rapprochement appeared to be derailed on Saturday as officials and clerics lined up to denounce the kingdom.For all the latest business news from the UAE and Gulf countries, follow us on Twitter and Linkedin, like us on Facebook and subscribe to our YouTube page, which is updated daily.
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