The Government agency revealed details of the South West Regional Planning Assessments for the railway system as it looks to improve the network over the next 20 years.

It comes after figures showed that about 41,000 trips are made on the south west's rail network on an average weekday.

Nearly half of these trips are made to and from places outside the region.

Passenger rail journeys in the region have increased by 42 per-cent between 1995 and 2003 - a slightly higher level of growth that the national average.

The heaviest demand within the region is on the route from Bristol to Bath.

There is also sizeable demand for travel between Swindon and Bristol.

As a result, one of the main objectives from the Department for Transport is to introduce higher capacity trains between London and the south west to meet the forecast growth in the demand.

The plans focus on London, Swindon, Bristol and Bath.

The report says minor infrastructure enhancement may be required between Swindon and Kemble for the South Wales services at Swindon and this is classed as a medium and long-term priority.

Proposals are also being considered to make better use of capacity for freight services and to introduce earlier outbound peak services from London to the south west.

It is also hoped that smart card technology can be improved to encourage more travel during off-peak periods.

Swindon-based rail operator First Great Western said it was unable to comment on the new rail strategy as its own franchise only runs for the next 10 years.

But a spokesman said the company was committed to working with the Government to improve the network.

One of the Government's objectives on future issues involves improving connections within the south west and between the region and the rest of the UK.

The development strategy is the latest in the series of 11 Regional Planning Assessments covering England and Wales.

The objective of the assessments is to identify the medium to long-term priorities for the railway at regional level, in the context of regional planning policies and strategies.

With population set to grow in the south west, the railway is seen by the Government as an important part of the transport system as it links key centres to the rest of the UK, particularly to London and the south east.