Under proposals put forward by the London Exchange yesterday, the stock market would open for trade at 8am, rather than the current 9am, and would continue to close at 4.30pm.
A spokesman for the London Stock Exchange, which last year announced plans to link up with its counterpart in Frankfurt, said the decision was part of the wider London-Frankfurt push for a pan-European exchange.
In a statement with Deutsche Borse, its Frankfurt partner, the London Stock Exchange said: "Today's proposals are one further link in the chain leading to our goal of barrier-free trading in Europe."
Deutsche Borse said it intended to synchronise its trading day with the proposed London hours by opening 30 minutes later than at present and closing 30 minutes later.
The proposed London changes, which are expected to come into force later this year, are the second set of alterations in less than a year.
Last summer the opening time was moved from 8.30am to 9am in an attempt to curb volatility in share prices early in the morning caused by low trading volumes.
A spokesman for the London Exchange said that although volatility would be monitored under the new trading hours, market liquidity had improved considerably since the summer. He said: "Analysis of the order book does vary from day to day, but overall, liquidity is much better, particularly at open and close."
The exchange also plans to scrap the maximum limit on sizes of trade and to consult on a series of longer-term changes.
These include using auctions at market opening and close as well as during the trading day, extending the electronic order book to mid-cap stocks, and shortening the settlement cycle.
The London/Frankfurt move follows recent indications by the New York Stock Exchange that it would open earlier in order to trade European stocks, a likely first step towards round the clock trading.