Saudi Arabia has invested a massive $3.5 billion of its sovereign wealth fund in United States ride-hailing service Uber .

The investment comes as part of Uber's most recent financing round, bringing the companies value to $63.5 billion. This makes Uber the most highly valued venture capital-backed company in the entire world. Saudi's investment brings the company's total balance sheet to more than $11 billion, including cash and debt, according to Uber.

Yasir Al Rumayyan, managing director of the Saudi fund, will join Uber's board along with the investment.

"We appreciate the vote of confidence in our business as we continue to expand our global presence," Uber CEO Travis Kalanick said, according to Financial Times . "Our experience in Saudi Arabia is a great example of how Uber can benefit riders, drivers and cities and we look forward to partnering to support their economic and social reforms."

The Saudi investment comes as the company aggressively targets the Middle East and North African market. Currently Uber operates in nine regional countries (Bahrain, Egypt, Israel, Jordan, Lebanon, Morocco, Qatar, Saudi Arabia and the United Arab Emirates) and 15 cities, previously saying it planned to invest $250 million in the region.

According to Uber, it has some 395,000 riders within the region as of the first quarter of 2016. This marks an increase of 500 percent from just 19,000 active riders a year ago. It also has 19,000 active drivers, up from four-fold from the first quarter of 2015. Within Saudi Arabia alone, Uber has some 130,000 active users, some 80 percent of whom are women.

As is the case in other global markets, Uber faces regional competition from similar services such as Careem, which operates in 20 cities throughout the region.