Muslim pilgrims circumambulate the Kaaba, Islam's holiest shrine, at the Grand Mosque in Saudi Arabia's holy city of Mecca on September 3, 2017, during the annual Hajj pilgrimage. (AFP Photo)

RIYADH, Oct. 2 (Xinhua) -- Saudi Arabia's sovereign wealth fund is increasing investment in the holiest sites in Mecca and Medina in a bid to host more pilgrims, the fund source said on Monday.

Saudi Arabia's sovereign wealth fund is establishing two new companies to increase the number of pilgrims that the kingdom can host at two of Islam's holiest sites in Mecca and Medina.

Saudi investments at the holy sites are aimed at boosting revenues from tourism and offsetting the impact of lower oil prices.

The kingdom's Public Investment Fund said the companies, Rou'a Al Haram and Rou'a Al Madinah, will develop residential and commercial areas around the Grand Mosque in Mecca and the mosque in Medina where the Prophet Muhammad is buried.

The fund said on Monday that the new companies will help the kingdom accommodate between 25 million to 30 million pilgrims a year.

The companies will develop 150,000 hotel rooms in both cities near the holy sites.