Google is to cut 4,000 jobs from its Motorola Mobility phone business.
The reductions represent about 20% of Motorola Mobility's 20,000 employees, and two-thirds of the cuts will be outside the US.
Google said the changes are intended to make the unit profitable, but warned that investors should expect the business' revenue to fluctuate over the next few quarters.
"While lower expenses are likely to lag the immediate negative impact to revenue, Google sees these actions as a key step for Motorola to achieve sustainable profitability," the company said.
Google said it also will shift Motorola Mobility's focus from simple wireless phones to more profitable devices.
Google completed its 12.5 billion dollar (£8 billion) purchase of Motorola Mobility in May. The deal, the most expensive in the company's history, expanded it into the hardware business and pushed it deeper into the mobile business, a market it entered four years before with the debut of its Android software.
The phone pioneer had struggled in the years leading up to the deal. It had not produced a mass-market hit since it introduced the Razr in 2005 and its market share has fallen.