Irvine-based Mazda North American Operations is offering an unspecified number of voluntary buyout packages to employees.

Employees must submit an application by April 16 for consideration, with the company expected to make final decisions by April 27.

Mazda will lay off some workers if it does not receive a sufficient amount of volunteers for the buyout program, spokesperson Jeremy Barnes said.

The buyouts and involuntary layoffs are part of a three-phase restructuring process that will be implemented this year.

A “redeployment” phase will include organizational changes, and could also inlcude layoffs depending on what occurs during the voluntary separation period, Barnes said.

Mazda North American Chief Executive Jim O’Sullivan cited a “challenging business environment” as the reason for the restructuring.

The troubles stem from Mazda North American’s Japan-based parent Mazda Motor Corp.’s expected $1.2 billion net loss for the 12 months ending in March, according to trade reports.

The North American business appears to have fared well over the past few years, with sales in 2010 and 2011 up from the previous year.

Mazda North American reported a strong start to this year with January sales up 68.2% to 23,996 vehicles.

That was followed up with a 32.3% gain in sales last month to 25,651 vehicles.

Mazda is the second largest automaker with operations here, with 434 workers, according to a Business Journal list.