The Hong Kong stock exchange is proposing the introduction of a pre-opening session to help boost volume and stabilise prices. Deputy chief executive Alec Tsui Yiu-wa said the exchange wanted to introduce a pre-opening session from 9.30 am to 10 am, which it claims would help establish firm opening prices and avoid mis-quoted transactions. A stock exchange consultation paper released yesterday says: 'Initially, the pre-opening session will operate from 9.30 am to 9.45 am for order entry. Matching will take place between 9.45 am and 10 am after which the market will be open for continuous trading.' An equilibrium price, calculated during the pre-opening session, would then be used as the opening price, the paper said. The stock exchange has also suggested an evening session from 5pm to 6pm, when trading of Hong Kong stocks in London would normally be at its peak. 'It might recapture some of the trade supposedly lost to the London market and hence would generate more local trades. The competition will mean it is up to the investor to decide in which market to execute the order,' Mr Tsui said. Trading hours now are between 10am and 12.30pm, with an afternoon session between 2.30pm and 3.55pm. Hong Kong stocks can be traded in London from 4.30pm, Hong Kong time. 'It is the exchange's mission to maintain and enhance the position of Hong Kong as an international financial centre so that it can meet the challenges of the future,' the consultation paper says. Mr Tsui said pre-opening sessions were used in overseas markets and helped eliminate extreme price fluctuations during the opening session - especially on newly-listed stocks. Hong Kong Stockbrokers Association chairman Chu Chung-tin said the proposal would be a burden for small brokers, who may find it too expensive to hire people for the extra trading hours. Critics have also suggested it would be possible to manipulate the pre-opening session by removing orders immediately before the close of the order input period, causing a sudden change in the opening price. Another controversial proposal suggested by the exchange is the connection of brokers' and clients' computer terminals to the exchange auto matching system. Under this proposal, brokers' second terminals would be modified to act as a gateway to the system, meaning investors would no longer have to telephone their broker but could instead directly input orders through their computer terminals. Mr Chu said changing the computer linage would devalue the price of exchange seats as the big houses would no longer need to buy new seats if they wanted more terminals. Mr Tsui said consultation on the proposals would be completed by March 21 and a report would be completed within the next few months. The proposals are expected to be implemented in two years time.