Saudi Arabia has said it is breaking off diplomatic ties with Iran, amid an escalating row between the two countries over the Saudi execution of Shia cleric Sheikh Nimr al-Nimr.

Speaking at a press conference on Sunday, Saudi Foreign Minister Adel al-Jubeir demanded that Iran’s diplomatic mission to leave the country within 48 hours. He said Riyadh would not allow the Islamic Republic to undermine the Sunni kingdom’s security.

Foreign Minister: the Kingdom Cuts its Diplomatic Relations with Iran and Withdraws Employees of the Saudi Embassy and Consulate in #Iran . — SPAENG (@Spa_Eng) January 3, 2016

According to Dubai-based al-Arabiya, Saudi Arabia has evacuated its diplomats from Tehran.

Iranian protesters stormed and set ablaze the Saudi embassy in Tehran on Saturday night during a rally in condemnation of Riyadh’s execution of the cleric.

Iran’s Supreme leader Ayatollah Khamenei called Sheikh Nimr a “martyr” who had acted peacefully.

He also warned Saudi Arabia that it will face “divine retribution” after officials executed the Shia cleric on Saturday, an act which has angered Shia Muslims throughout the Middle East.