Major Japanese automakers on Monday reported falls in new car sales in China in 2012, attributing the decline to souring ties between the two countries.

Toyota's new car sales in China fell 4.9 percent last year from 2011 to 840,500 units, while Nissan posted a-5.3 percent fall to 1, 181,500 units, according to companies' reports.

Both Toyota and Nissan said that it was their first sales decline in China since they fully entered the Chinese market in 2003, when they established joint ventures with local partners.

Meanwhile, Honda Motor Co. also said that its sales in China were down 3.1 percent in 2012 compared with 2011.