The US embassy in Saudi Arabia warned today that "terrorist" groups in the kingdom may strike during the coming Muslim holy month of Ramadan after Britain said attacks may be in the "final stages" of planning.
Saudi officials vowed to thwart any "terror" plots in the oil-rich kingdom, birthplace of al Qaeda leader Osama bin Laden. The fasting month of Ramadan is expected to start on Sunday, depending on the sighting of the new moon.
A US diplomatic advisory issued in the Saudi capital Riyadh said: "The embassy continues to receive information that terrorist groups within the kingdom are still active and planning future operations.
"It is the embassy's assessment that terrorist groups may place special operational significance on the upcoming month of Ramadan and American citizens are therefore urged to be particularly vigilant during this time."
Saudi authorities have intensified a crackdown on Muslim militants since suspected al Qaeda suicide bombers hit expatriate housing compounds in Riyadh in May, killing 35 people including nine Americans.
It has arrested nearly 600 people since then. "Saudi security forces are working hard to foil any terrorist organisation and have uncovered several cells in past weeks and thwarted all their plans to destabilise security," said a Saudi official without identifying the possible targets.