Renesas Electronics Corp. plans to close two design and development centers by September 2015 as part of the struggling chipmaker's major overhaul of domestic nonmanufacturing facilities, company sources said.

The design and development offices are located in Kawasaki and Sagamihara, Kanagawa Prefecture, the sources said Thursday.

In total, Renesas plans to transfer about 6,000 workers, or more than half of those employed at domestic facilities subject to the overhaul, according to the sources.

Management has already asked the labor union for consultations over the matter, they said. The company plans to move its head office in central Tokyo.

Renesas is also planning to slash 5,400 domestic jobs, or around 20 percent of its workforce, by the end of March 2016, and to elicit early retirements to accelerate its restructuring efforts.