Microsoft CEO Satya Nadella gestures on stage while speaking during a press briefing on the intersection of cloud and mobile computing Thursday, March 27, 2014, in San Francisco. Microsoft unveiled Office for the iPad, a software suite that includes programs such as Word, Excel and PowerPoint, and works on rival Apple Inc.'s hugely popular tablet computer. (AP Photo/Eric Risberg)

(Reuters) - Microsoft Corp is planning its biggest round of job cuts in five years as the software maker looks to integrate Nokia Oyj's handset unit, Bloomberg reported, citing people with knowledge of the company's plans.

The reductions, expected to be announced as soon as this week, could be in the Nokia unit and the parts of Microsoft that overlap with that business, as well as in marketing and engineering, Bloomberg reported.

Since absorbing the handset business of Nokia this spring, Microsoft has 127,000 employees, far more than rivals Apple Inc and Google Inc. Wall Street is expecting Chief Executive Satya Nadella to make some cuts, which would represent Microsoft's first major layoffs since 2009.

The restructuring may end up being the biggest in Microsoft history, topping the 5,800 jobs cut in 2009, the report said.

Some of the job cuts will be in marketing departments for businesses such as the global Xbox team, and among software testers, while other job cuts may result from changes Nadella is making to the engineering organization, Bloomberg reported.

Last week, Nadella circulated a memo to employees promising to "flatten the organization and develop leaner business processes" but deferred any comment on widely expected job cuts at the software company.

Nadella said he would address detailed organizational and financial issues for the company's new financial year, which started at the beginning of this month, when Microsoft reports quarterly results on July 22.

Microsoft could not be immediately reached for comment outside regular business hours.

(Reporting by Supriya Kurane in Bangalore; Editing by Gopakumar Warrier)