UPDATE 1- Honda, Guangzhou Auto mull capacity expansion-exec

* Honda, Guangzhou Auto may expand JV capacity by a third

* Guangzhou Auto sees 2009 sales up 12-13 pct

* Guangzhou Auto sees capacity top 1 mln units in 2011 (Adds quotes, details)

By Fang Yan and David Lin

SHANGHAI, Nov 12 (Reuters) - Honda Motor (7267.T) and Guangzhou Automobile may expand the capacity of their China plant by a third next year to meet robust demand in the world's largest market, chairman of the Chinese automaker said on Thursday.

The No. 2 Japanese automaker and its partner operate 2 plants making Accord, City Odyssey and Fit models in south China, with a combined capacity of 360,000 units.

"Our second plant is smaller with only 120,000 units. We may double the capacity next year," Zhang Fangyou told Reuters on the sidelines of an industry forum in Shanghai.

A spokesman with Honda's China operations said the expansion plan is under consideration but no final decision has been made so far.

China is a major bright spot this year as the government's policy incentives bolstered automobile demand, making the country a safe heaven for global automakers, battered by a sharp-than-expected industry downturn.