Internet major Google is phasing out its internal use of Microsoft Windows operating system due to security concerns, which arose mainly after its China operations were hacked, a media report has said.

The report by the UK daily 'Financial Times', citing several Google employees, said the internet giant is "phasing out internal use of Microsoft's ubiquitous Windows operating system because of security concerns."

The directive to move to other operating systems had begun in January at Google, after its Chinese operations were hacked.

The move can effectively end the use of Windows at Google, which employs more than 10,000 workers internationally, the report added.

"We're not doing any more Windows. It is a security effort," FT quoted a Google employee as saying.

Another google employee said that many people have been moved away from [Windows] PCs, mostly towards Mac OS, following the China hacking attacks.

New people hired at Google are now given the option of using Apple's Mac computers or PCs running the Linux operating system.

In early January, some new employees were still being allowed to install Windows on their laptops, but it was not an option for their desktop computers, the report added.

Windows is known for being more vulnerable to attacks by hackers and more susceptible to computer viruses than other operating systems.

In addition to being a semi-formal policy, employees themselves have grown more concerned about security after the China attacks, the report said citing an employee.