Several hundred people marched in Hong Kong Sunday, opposing a controversial government scheme that allows mainland Chinese cars into the territory, further escalating tensions between the two sides.

About 300 protestors in the busy downtown area chanted slogans "(we) oppose mainland cars roaming in Hong Kong freely!" and waved banners that read "No, no, no, mainland Chinese cars".

The first stage of the scheme, set to be implemented in phases starting next month, allows Hong Kong drivers to apply to take their vehicles to mainland China. The quota is set at 50 cars per day.

The government said it has yet to set the timetable for the second stage, which allows drivers from the Guangdong province in southern China to apply to drive in Hong Kong.

One participant on the march, Shirley Cheung, who has been driving for 20 years, told AFP: "I am strongly against the plan because Hong Kong drives on the left side of the road, mainland China on the right."

"We have enough traffic accidents as it is, we don't want more!" she said.

Another participant, Alex Kong, complained the government did not consult the public before going ahead with the scheme.

Secretary for Transport and Housing Eva Cheng sought to placate angry locals, telling reporters it was "just a trial scheme".

"We will review (the plan's) viability and proceed gradually with caution, taking into account various factors including safety and the capacity of road networks."

Tensions between Hong Kongers and their mainland counterparts have spiked recently after Chinese professor Kong Qingdong called locals of the former British colony "dogs" and "bastards".

In retaliation, an anonymous group of Hong Kongers published a full-page advert demanding action to stop mainland Chinese "infiltration" of the territory, showing a huge locust overlooking Hong Kong.

Mainlanders are a key source of revenue for Hong Kong, but there is growing discontent over the thousands of Chinese who come to give birth in the territory every year, taking up limited beds and pushing up costs.

Hong Kong's seven million people are guaranteed a high degree of autonomy and civil liberties not seen on the mainland.