The US has announced that it is allowing non-essential diplomatic staff to return to Saudi Arabia.
Saudi security forces outside a compound in Khobar that was attacked in May
They were ordered to leave last April because of concerns that Islamist militants were planning to attack American and other Western interests.
The US state department said it was still warning American citizens to avoid travelling to Saudi Arabia.
Family members are not, for the time being, allowed to accompany the returning diplomats.
US officials said the security situation in Saudi Arabia had improved over the past four months, but added that Saudi officials acknowledged that more time was needed to neutralise the threat of terrorism.
The US has an embassy in the capital Riyadh, and consulates in Dhahran and Jeddah.
Since May last year, the Saudi Arabian security forces have been locked in confrontation with militants suspected of having links to al-Qaeda.
About 100 people have been killed, most of them foreigners, in a string of attacks in different parts of the country.
Earlier this month, Irishman Anthony Higgins was shot dead in Riyadh.
In June, US aeronautical engineer Paul Johnson was kidnapped and decapitated by his captors shortly afterwards.