Fiat will build gearboxes in China as part of its plans to produce cars there next year, a media report said.

The deal was due to be announced on Friday during the visit of China's vice president Xi Jinping to Rome, a source told Reuters.

Fiat signed a joint venture in 2009 with Hong Kong-listed Guangzhou Automobile Group to make cars in China.

The gearboxes will be produced in partnership with Guangzhou and China's Hangzhou Advance Gearbox Group, the source said, without disclosing financial details.