BEIJING -- Lawmakers on Wednesday called on market regulators to step up supervision and stipulate heavier penalties for violators once a stock listing reform takes effect.

Legislators are set to approve a State Council proposal on the current approval-based listing system on the Shanghai and Shenzhen bourses, which will see it change to being registration based.

They are deliberating the amendment at the week-long bimonthly session of the National People's Congress (NPC) Standing Committee.

Under the current system, new shares are subject to approval by the China Securities Regulatory Commission (CSRC), which controls the timing and price.

Once adopted, the new system will allow the bourses to take over IPO approval, and clear the waiting list backlog.

More details are to be hammered out by the State Council, but the stock market regulator had said the new system will emphasize information disclosure while allowing the market to play a bigger role in determining price, timing, and the scale.

While the regulator will no longer play a key role in IPO approval, it is expected to step up measures against fraud and information disclosure.

During panel discussions on Wednesday, lawmakers urged the regulator to enhance post-registration supervision.

"While lowering the threshold for market access, we must step up supervision, and particularly, penalties for violations," said legislator Du Limin.

He suggested that listed companies found to have registered via fraudulent means should be subject to compulsory de-listing, adding that investors' rights should be protected in the process.

Li Shenglin, another lawmaker, said reinforced post-registration supervision is the pretext of IPO reform. Li also called on the top legislature to speed up amendments to the current Securities Law.