Saudi Arabia has barred more than 269,000 people without permits for the annual Hajj pilgrimage from entering Mecca this week, authorities said, as the world's largest annual gathering of people has officially begun.

A Saudi government spokesperson says more than 1.5 million foreign pilgrims are in the country for this year's Hajj.

The start of Dhul Hijjah leads to the Hajj, a holy pilgrimage for Muslims, and Saudi Arabia has confirmed the Hajj start date. Here's when it begins.