China's September vehicle sales rose 3 percent from a year earlier, the slowest pace in 19 months, dragged down by sluggish demand for commercial vehicles.

Vehicle sales totaled 1.98 million units last month, the China Association of Automobile Manufacturers said. Passenger vehicle sales rose 6 percent while commercial vehicle sales slumped 16 percent.

During the first nine months of 2014, China's vehicle sales rose 7 percent from a year earlier.

The manufacturers association has forecast that the market will expand 8 percent this year, slowing from last year's 14 percent pace.

"China already has a huge auto market, and with more cities expected to restrict auto sales to fight pollution, it's natural for growth to slow down," said Li Xiangfeng, an analyst at Shanghai-based consultancy ISE.

"The market cannot grow at double-digit pace forever," he said, adding that the slump in commercial vehicle sales might be caused by a slowing economy.

In September, Japanese carmakers Nissan Motor Corp. and Honda Motor Co. each posted its third consecutive monthly decline in China sales. Nissan's deliveries slid 20 percent and Honda's volume was off 23 percent.

Nissan attributed the decline to sluggish sales of commercial vehicles and increased competition while Honda said dealers had been clearing inventory ahead of the launch of two new models this year.

On the other hand, sales of German brands have continued to be robust. Premium carmaker BMW posted 18 percent growth during the first nine months while Mercedes-Benz said its China sales jumped 31 percent in September.

Volkswagen AG's Audi premium brand posted a 13 percent increase in China sales in September.