A long-awaited connection from the terminal to Luton Airport Parkway station could be built by 2020 if plans to be submitted in the autumn are given the go-ahead.

The construction will not bring mainline trains to the airport’s door, but it will remove the bus journey from the railway station, which is just over a mile from the airport but is often hampered by queuing traffic.

It is hoped that work will start next year, with the opening coming two years after the upgrade to the Bedford to Brighton Thameslink line, which serves the airport through London.

The airport also hopes to persuade other train companies to stop more of their services at the station to provide a regular 30-minute journey to London St Pancras station.

The local council, which owns the airport, will fund the extension, hoping to put an end to the problem of accessing the airport, which is seen as its major drawback.

A separate investment programme aims to grow passenger numbers from 12 million to 18 million by 2026 following a £100 million programme of building.