Swansea rail electrification: Campaigners' new hopes
Campaigners meet later to make a final bid to make the case for electrifying the main Paddington-south Wales railway line as far as Swansea.
The £1bn electrification of the line to Cardiff was confirmed last year.
Politicians, academics and business leaders in south-west Wales have called for an extension of the project to Swansea to help boost trade.
The UK government is set to announce in the coming days whether or not that will be extended further west.
The Department for Transport has said it was considering the business case for electrification in south Wales.
In May this year, Welsh Secretary Cheryl Gillan said the UK government must see a business case before it can electrify the line from Paddington to Swansea.
The meeting at Swansea Civic Centre comes days after a report commissioned by the Welsh government called for two "city regions" to be developed around Cardiff and Swansea to boost economic performance.
One of the recommendations was that the Welsh government continues to lobby the UK government for the electrification of the rail main line from London to Swansea.
Last month, Transport Minister Carl Sargeant officially opened Swansea High Street Station following a £7.6m upgrade.
More than 1.6m passengers pass through the station every year.
On Thursday plans for a new £500m Heathrow rail link were approved offering the prospect of direct trains to the airport from south Wales.