A Saudi criminal court on Tuesday sentenced one citizen to death and seven others to jail on charges of treason and spying for the kingdom's arch-nemesis Iran, state television reported.

The Saudi sentenced to death was accused of "betraying his country and offering intelligence to Iran", Al-Ekhbariya television said on Twitter. Seven others were sentenced to a total jail term of 58 years for having "associated and cooperated with people working in the embassy of Iran", it added.

The broadcaster did not identify the people nor explain with which Iranian embassy they were accused of cooperating. Sunni powerhouse Saudi Arabia snapped diplomatic relations with Shiite-dominated Iran following 2016 attacks by demonstrators on its missions in Iran after the kingdom executed revered Shiite cleric Sheikh Nimr al-Nimr.

Saudi Arabia, home of the birthplace of Islam, has been at odds with Iran since the Islamic revolution of 1979 ushered in a Shiite theocracy and set the two countries on a collision course. Tensions have risen in recent months after a series of attacks on oil tankers in the Gulf and Saudi oil installations, incidents that roiled global energy markets last year.

Both Washington and Riyadh have accused Iran of being behind those attacks, a charge denied by Tehran.