<sod >The breakdown in relations is believed to be due to Saudi Arabia's execution of Sheikh Nimr al-Nimr, an Iranian cleric and prominent critic of the Saudi Arabian government.< eod>< sod > The breakdown in relations is the culmination of a conflict caused by Saudi Arabia's execution of Sheikh Nimr al-Nimr, an Shia cleric and prominent critic of the Saudi Arabian government, and the storming of the Saudi embassy in Iran that resulted.< eod>