Microsoft Corp. is infusing $100 million into Uber Technologies Inc. in the cab-hailing company's latest round of fundraising.

The investment deal finalized on Friday is part of a $1 billion new financing to Uber, said people privy to the deal, but who declined to be identified, according to Bloomberg.

Uber spokeswoman Kristin Carvell said the company filed to authorize this new funding more than two months ago and did not give more details. Microsoft is also not commenting.

The new funding will boost the five-year-old San Francisco company's capital to more than $5 billion with a valuation of $51 billion as it aggressively expands in markets abroad. Its planned global expansion covers 300 cities in 57 countries, according to MarketWatch.

Investors now value Uber at $51 billion based on the latest round of financing, according to The Register. That surpassed the $45 valuation reached by Xiaomi in December and took the title from the Chinese electronics company as the world's most valuable startup.

Seven months ago, Uber was valued at $41 billion.

Microsoft's investment in Uber is the latest transaction of the software giant with the taxi-hailing app maker.

In June, Microsoft sold a portion of its mapping technology Bing Maps to Uber for an undisclosed amount, according to The Register. Uber offered jobs to 100 employees of the mapping unit to run the software.

Among the companies that joined the latest round of fundraising for Uber is Indian media conglomerate Bennett Coleman & Co.

Uber's smartphone application connects drivers with people who need a ride and enables users to arrange and schedule transportation and/or logistics services with third party providers. Chief Executive Officer Travis Kalanick and Garrett Camp founded the company in 2009.