CHENGDU, China, Sept. 6 (Kyodo) — The territorial dispute between Japan and China in the East China Sea has dragged down sales of Japanese cars in China, with most Japanese brands seeing a plunge in sales last month, a senior executive of Nissan Motor Co. said Thursday.

Toshiyuki Shiga, Nissan's chief operating officer, made the observation to reporters while in the city of Chengdu, southwestern China, to attend a symposium of Japanese and Chinese automakers.

Anti-Japan demonstrations broke out in major Chinese cities last month, with some protesters vandalizing Japanese brand vehicles, after Japanese authorities detained a group of Chinese activists who landed on one of the Japanese-controlled Senkaku Islands in the East China Sea.

"It has been difficult for us to launch major sales campaigns, outdoor campaigns in particular," Shiga said.

While China has overtaken the United States as the world's largest automobile market, the pace of growth has shown signs of a slowdown, forcing sharper competition among Chinese and foreign car makers.

Speaking at the symposium, Shiga said Nissan is ready to cooperate with Chinese automakers to explore overseas markets, citing Africa, where Nissan has a modest market presence, as an area of cooperation.

Toyota Motor Corp. Vice President Atsushi Niimi gave a rosy projection of car sales in China, saying Toyota is aiming to boost its annual sales volume in China to between 1.5 million and 1.8 million cars by 2015, up from 900,000 in 2011.

The sales target would raise Toyota's market share in China to 15 percent from the current 12 percent.