Australia and Britain warned on Monday that militants would soon strike in Saudi Arabia as the United States closed its missions in the world's biggest oil exporter for two days in response to threats.
Saudi Arabia, battling a two-year campaign of violence by supporters of al-Qaeda leader Osama bin Laden, said it had no solid information of any imminent attack.
But Australia's Department of Foreign Affairs told its citizens to avoid travel to the kingdom, saying militants might be planning attacks on housing compounds.
"We have received credible reports that terrorists are planning attacks in Saudi Arabia in the near future," the department said on its Web site.
"This follows other recent reporting suggesting that terrorists may be planning to attack residential housing compounds in Saudi Arabia."
The security warnings, combined with worries the United States may face a gasoline shortage, helped propel oil prices to another record high. U.S. light sweet crude was up 56 cents, at $62.87 a barrel, on Monday, reports Reuters.
But Saudi Interior Ministry spokesman, Major General Mansour al-Turki, said they had no intelligence on a possible attack in the near future.
"We can't dispel the possibility of a terrorist attack happening in the region," he said. "But we have no information about an imminent terrorist attack in the kingdom."
Militants loyal to Saudi-born al-Qaeda leader Osama Bin Laden have killed more than 90 foreign nationals and Saudi citizens and caused damage costing hundreds of millions of dollars since May 2003.
Saudi Arabia has come under pressure to curb extremism in the wake of the violence and there have been regular gun battles between Saudi security forces and militants, informs BBC.