Saudi Arabia is on alert for a possible Al Qaeda attack next week during hajj, the annual Islamic pilgrimage that draws millions of worshippers to the holy cities of Mecca and Medina, the country's interior minister said.

Prince Nayef did not mention any specific threat or intelligence indicating an imminent attack, but stressed that "the kingdom is capable of foiling, confronting, deterring any act."

Saudi Arabia has been effective in the past in countering Al Qaeda militants, who have publicly declared their desire to topple the kingdom's royal family. It was the Saudis who gave the West the key tip on two mail bombs recently intercepted after they were sent on planes from neighboring Yemen. Al Qaeda's Yemeni offshoot claimed responsibility for that plot.

"We don't rule out any possibility of something disturbing the security" of the pilgrims, Nayef said, while adding that authorities "are ready for anything that might take place. God willing, nothing will happen."

Interior Ministry spokesman Gen. Mansour al-Turki said Nayef was not referring to any specific information about an imminent Al Qaeda operation.

He also said authorities remain vigilant and have plans in place "to ensure the security and safety of all pilgrims."

The hajj begins on Nov. 15 and lasts for several days.