SAN FRANCISCO - US multinational tech leader Microsoft said Tuesday that it has agreed to extend its partnership with a Chinese internet data center service provider to offer world-class public cloud services to Chinese customers.

Microsoft's global technological leadership combined with the local operations expertise of 21Vianet, the Chinese leading carrier-neutral internet data center services provider in China, as well as Microsoft Azure and Office 365 operated by 21Vianet, have achieved unprecedented, robust three-digit growth for nearly four consecutive years in the world's second largest economy, Microsoft wrote in its official blog post Wednesday.

The cooperation model pioneered by Microsoft and 21Vianet has been recognized as an effective and successful method for a legal and compliant operation of international cloud services in China, it said.

Microsoft was the first international public cloud provider to bring its cloud technology to China in partnership with 21Vianet after it officially launched the Azure service, a cloud computing platform in March 2014.

Azure public cloud services have served more than 100,000 Chinese enterprise customers, attracting over 1,300 cloud partners and over 100,000 active Azure DevOps developers, 21Vianet said in a statement Wednesday.

The customers of Microsoft Azure include almost all of China's big names, ranging from established Chinese brands such as China's top home appliances manufacturer Haier, the primary Chinese computer leader Lenovo, and China's telecom giant Huawei, to emerging powerhouses such as smartphone manufacturer Xiaomi, bike-share company Mobike, and automobile manufacturer BYD.

About 1.2 million Chinese enterprise users and 20 million educational users are currently conducting their daily work using Office 365, the brand name that Microsoft uses for a group of subscriptions that provide productivity software and related services.

Office 365 operated by 21Vianet was launched in China in April 2014 and now ranks top place in China's SaaS market.

Huawei, Tencent, and Pactera currently use Office 365 operated by 21Vianet to empower their employees and optimize their daily business operations.

Since its establishment in 2013, 21Vianet's cloud operation and maintenance group for Azure and Office 365 in China has grown from dozens of people to one of the largest professional cloud operation and maintenance teams in China, 21Vianet said.

Microsoft CEO Satya Nadella announced in November 2017 that Microsoft Azure operated by 21Vianet will triple its capacity in China in the beginning of 2018.

Azure's enlarged capacity will make it easier for multinational companies to meet the needs of Chinese customers through the scale, power, and secure infrastructure of the Azure cloud, Microsoft said.

21Vianet operates in more than 30 cities throughout China, serving more than 4,000 hosting enterprise customers that range from internet companies to government entities, and from blue-chip enterprises to small- to medium-sized enterprises.