The United States has warned that new terrorist attacks in Saudi Arabia may be "imminent".
More than 30 people were killed in the Riyadh bombings
It announced it was closing its embassy in Riyadh and consulates in Jeddah and Dhahran from Wednesday, saying it had credible information about attacks planned against unspecified targets.
No decision has yet been made as to when the offices may reopen, but it would not be before Sunday, a message on the US embassy's website said.
The announcement follows a warning on Monday from Saudi Arabia's ambassador to Washington, who says he fears a major attack is imminent in either the US or Saudi Arabia.
Prince Bandar bin Sultan said the US and Saudi Arabia had picked up electronic "chatter" in the region and in other areas which indicated something else was being planned in addition to the suicide attacks that took place last week.
He said that a raid by authorities in the country earlier this month had uncovered huge quantities of explosives which could have caused even greater devastation than the attacks which left 34 dead, including nine alleged bombers.
"I think they were looking to do something more major than this," he told journalists on Monday.
"That would have taken out two blocks in the city if it had gone off accidentally. We're all wondering if it's the last [of the explosives] or is it the tip of the iceberg?"
Prince Bandar said that chatter picked up by Saudi and US monitors had indicated the Riyadh attacks were being planned but had not given information regarding a time or place.
He said the chatter had stopped almost completely two or three days before the attacks.
"I'm confident we'll get them in the end. But the question is, will it be early enough or not?" he said.
He also said that some Saudi officials believed that al-Qaeda - the network suspected of carrying out the bombings - had at some point been split over whether to attack the kingdom, the birthplace of its leader Osama Bin Laden, for fear of losing its intellectual base.
'Whatever it takes'
At the weekend, the US state department warned of a possible imminent terrorist attack in the western Saudi port of Jeddah.
And on Monday, a US consulate in eastern Saudi Arabia was closed to the public after a gunman was arrested outside its gates.
Saudi Arabia, which has been strongly criticised by Washington since the blasts, has pledged to do "whatever it takes" to uphold security.
Interior Minister Prince Nayef bin Abdul Aziz said the Saudi security forces were working closely with the US "in order to fight terrorism."
The suicide attacks came two weeks after the US announced it was withdrawing most of its troops from Saudi Arabia, where they were deployed during the 1991 Gulf War.