Plans to cope with growing demand on the railways have received a cautious welcome from Bradford rail groups.

Transport Secretary Alistair Darling outlined proposals for longer trains, more efficient timetabling and replacement of the Intercity 125s in a bid to tackle overcrowding.

Experts have warned that passengers may increase by 30 per cent over the next 20 years.

Mr Darling told a London rail conference the Government would next year set out solid plans. A rail White Paper is due to be published in 2007.

He said: "There are many ways to increase capacity; we need to consider them all - from train layout and length, timetabling efficiency and turnarounds, particularly at mainline stations, to the re-examination of gauge and looking at double-decker trains."

Bradford rail groups said they would reserve judgment on the announcement, which included consideration of a north-to-south high-speed rail link.

Councillor Christopher Greaves, Bradford spokesman for the West Yorkshire Passenger Transport Authority, said local problems must be tackled first.

"The double-deckers in Europe are a good way of getting extra capacity but, like much of what's been said, they're a long way in the future," he said. "A network can only work on a larger scale if local problems are put right first.

"A lot of Metro trains are overcrowded but there isn't the money for improvements. So it's OK having trains from Leeds to London but, if people can't get to Leeds, what's the point?"

Councillor Greaves said he was concerned rising prices risked putting trains beyond the reach of ordinary passengers who might instead choose the car.

Tim Calow, secretary of the Aire Valley Rail Users Group, said: "We are glad there is the start of a strategy for investment because, over the last few years, there's been absolutely no long-term planning.

"There was a plan for a service from Bradford to London which came to nothing. That shows a major problem with capacity that must be dealt with."

Peter Johnson, secretary of Wharfedale Rail Users' Group, said: "We welcome the Government's commitment but in the absence of firm promises and targets we remain sceptical.

"Our group is looking for sustained investment."

Bradford Rail Users Group is campaigning for improvements to Bradford's rail services and infrastructure, including better information about services, new stations and a cross-city link.

Environment pressure group Transport 2000 highlighted the line between Leeds and Manchester as one of the top ten "pinch-points" in the UK. It called for new signalling, extra capacity and platform extensions.

In his speech, Mr Darling said replacing the high-speed train fleet was one of the key projects being led by the Department for Transport and that a replacement would have to be environmentally friendly.