Bahrain said it had thwarted a plot to undermine security in the kingdom and neighbouring Gulf states, prompting claims the embattled royal family is alluding to Iranian involvement to justify its violent quelling of pro-democracy protests last week.

Analysts and diplomats on the ground have during the past couple of months reiterated there is little evidence Iran has played a role in the turmoil.

But there are concerns that last week’s crackdown on protesters could trigger a response from Iran after Gulf forces arrived in the kingdom.

Last week, troops from Saudi Arabia and police from the United Arab Emirates arrived in Bahrain in a show of support for the regime.

A security crackdown has left at least 13 protesters dead and hundreds wounded since demonstrations first started on February 14. Skirmishes between Shia youths and security forces continue to break out in villages outside Manama, the capital.

“An external plot has been fomented for 20 to 30 years for the ground to be ripe for subversive designs,” King Hamad bin Isa al-Khalifa said late on Sunday. He said the plot, which could have spilt over to other Gulf Arab states, had failed, according to the official news agency.

Hints at foreign involvement have usually been a reference to Iran.

Opposition parties in Bahrain, primarily comprising the majority Arab Shia population, have continually rejected claims they are taking orders from Iran.

“This is typical rhetoric from the government,” said Theodore Karasik, head of research at the Institute for Near East Gulf Military Analysis, a Dubai-based think-tank. “Most people know it just isn’t true.”

The Shia-dominated pro-democracy movement, which had congregated at the now-demolished Pearl roundabout, has been at pains to reduce sectarian divisions.

One of the political leaders arrested after last week’s crackdown, Ebrahim Sharif of the secular, leftist Waad party, is Sunni and arguably the most moderate among the opposition.

Nonetheless, Bahrain, where a minority Sunni leadership dominates a majority Shia population, has become a sectarian battleground in the past couple of months.

Bahraini state-controlled broadcasters and newspapers have fanned the flames of religious differences in recent weeks, while Shia religious leaders and parties in Iran, Iraq and Lebanon have weighed in on the kingdom’s opposition clampdown.

The government has said the door is open to those pursuing political reform, but the opposition says talks are impossible in the current environment of arrests and beatings by security forces.

Copyright The Financial Times Limited 2018. All rights reserved.

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