However, it also emerged that about 1,500 households in the latest competition trial in Kent and Sussex, which began earlier this month, have complained about problems with the process, casting doubt on whether an accelerated national programme would be trouble-free.
Ian Lang, President of the Board of Trade, announced changes to the existing legislation, which said national competition cannot start before 1998. The provisional timetable involves the next phase, including Scotland into North-east England, beginning in the autumn with five further stages ending with Greater London the following April.
Most independent gas supply companies taking part in the first two trials in the south of England have been strongly pushing for a quicker timetable. Caroline Harper, managing director of Amerada Hess Gas, said she "wholeheartedly supported" the move.
The decision also represents a victory for Clare Spottiswoode, the industry regulator, who has pressed to speed up competition. So far choice has been extended to about 2 million homes in the South, of which more than 250,000 have moved from British Gas, lured by discounts of up to 20 per cent off bills.
British Gas's pipeline operation, TransCo, argued the new October target represented a "considerable challenge" and said it still preferred to start the process no earlier than next April. The DTI said its new timetable was "subject to the readiness of computer systems", a reference to TransCo's doubts about whether it can speed up the introduction of new computer systems in each of the next phases which track customers as they switch supplier.
The Gas Consumers Council warned problems in the latest south-east trial could hold up competition. The GCC revealed that hundreds of households in Kent and Sussex have either been wrongly moved from British Gas to a new supplier, or have not been switched to a new gas company despite signing a new contract.
Sue Slipman, GCC director, said she suspected either TransCo or the new suppliers had mixed up the customers' addresses and meter numbers.
She added: "We don't think this was down to fraudulent doorstep selling."