The Consumer Council on Monday said there should be more insurance options for motorists driving north, after finding that existing schemes provide the minimum protection but with markedly varying costs.

Drivers intending to cross the border from Hong Kong must buy compulsory motor insurance required by the mainland before applying for a temporarily licence, or an equivalent top-up cover under the "unilateral recognition" policy with local insurers.

The watchdog looked at a dozen local companies offering such plans and found there's a nearly 40 percent gap in premiums, although they offered the same indemnity limit of 200,000 yuan.

Among 11 insurers listing out the charges, the annual premiums for cars with less than six seats ranged from HK$832 to HK$1,159.

Prices for vehicles with six to eight seats are between HK$963 and HK$1,342 a year.

The watchdog said the insurance industry, relevant regulatory bodies and government departments should actively consider offering more diversified motor insurance products with higher insured amounts.

"We are delighted to hear from the Insurance Authority that there are some insurance companies already developing more comprehensive and better products, for example, some insurance companies are increasing the coverage on the medical side, which is very essential, because medical costs could be substantial," said Gilly Wong, the council's chief executive.

The council also urged motorists to buy extra third-party liability insurance to enhance their protection, but cautioned that there were differing concepts regarding these types of policies locally and on the mainland.

It noted that, unlike in Hong Kong, third-party liability policies on the mainland do not cover passengers on board, but rather others who suffered injuries, death or property loss that was caused by the vehicle.

A motorist should purchase another insurance policy for "persons on board liability" to extend coverage for passengers, the council added.