April 7 (Reuters) - Some Western and Saudi firms in Riyadh have extended work-from-home advisories this week, five people familiar with the matter said, amid concern over a looming U.S.-imposed deadline
for Iran to open the Strait of Hormuz or face "hell".
In Gulf states, which have borne the brunt of Iran's attacks since the war began on February 28, many fear a U.S. escalation would see Iran further target critical and civilian infrastructure in the Gulf in response.
The advisories, sent out on Monday and Tuesday individually by companies via email or text, affect work in Riyadh's King Abdullah Financial District, Faisaliah Tower, Business Gate and Laysen Valley, the people said.
These locations host offices for major U.S. banks and tech firms such as Microsoft and Apple, but also Saudi entities, including the sovereign wealth fund.
Employees were first told to work from home at the beginning of last week, the people said, after Iran threatened to strike major U.S. tech firms in the region in response to U.S.-Israeli attacks and assassinations.
The Saudi government media office did not immediately respond to a request for comment.
Saudi has faced hundreds of Iranian drone and rocket attacks since the war began but says it has intercepted the vast majority. It has been less affected than other Gulf states, such as the UAE and Kuwait.
On Tuesday, Saudi Arabia said it intercepted and destroyed seven ballistic missiles launched towards its Eastern Region, with debris falling near energy facilities. Iran's semi-official Fars news agency said a petrochemical complex in Saudi Arabia's Jubail industrial city was attacked.
(Reporting by Reuters;Editing by Alison Williams)
