One of the main train operators out of Brighton Station has promised that it will run more 12-carriage trains by the end of the year.
First Capital Connect gave the assurance in a meeting with Brighton Pavilion Green MP Caroline Lucas.
She met senior managers at First Capital Connect to discuss the quality of train services running in and out of Brighton.
And she highlighted a range of concerns raised by local residents, such as overcrowding and punctuality.
She said: “This meeting with First Capital Connect was a good opportunity to put forward some of the issues highlighted by my constituents in recent meetings and correspondence.
“I am encouraged by the assurances given by the train company that capacity on the line between Brighton and Bedford will be increased by December 2011 – and that new rolling stock is due to be introduced in 2015.
“I hope that some of the other issues raised in the session will also be addressed.”
Paul Oxley, media and stakeholder manager at First Capital Connect, said: “Our meeting with Caroline was extremely productive, and covered all major aspects of our services including customer information, performance and the Thameslink programme.
“There is a lot to come with our first 12-carriage trains this December and we look forward to working with Caroline in the future in providing the best possible service.”