Faster Norwich to London trains will boost East Anglia's economy by �2.5bn, experts have estimated – but only five minutes are expected to be knocked off travel times by 2020.

A new report today reveals around �395m is needed to revamp the Great Eastern Main Line (GEML), and provide more services per hour, extra seats for passengers and ensure trains travel at speeds of at least 110mph by 2031.

Officials hope this research will further boost their campaign to convince the government to invest extra cash in the region's major railway line.

The report is launched in Essex today just hours before Norfolk's bid for better transport links continues at Westminster.

An A47 delegation is to meet transport minister Stephen Hammond, pictured, this evening.

The GEML Vision Group's study, backed by Norfolk County Council, explains now is the time for the region to influence government spending, ahead of the award of a 15-year contract to operate services on the line.

Train operator Greater Anglia says it expects travel times will decrease by five or more minutes by the end of 2019, while Norwich in 90 is an aspiration for the future.

The GEML report also states there will be 5,100 fewer seats than required during the busiest morning peak hour by 2031 if no changes are made to the whole network.

The number of peak services between Norwich and London could also increase from seven to nine, or even 10 depending on demand.

The three main funding sources are noted as fares, government subsidy and private sector investment.

The latter includes councils using money from housing development charges, known as the community infrastructure levy, or other agreements made for community cash when planning applications are approved.

The improvements are also estimated to provide �2.5bn of economic benefits to the east over a 60-year period.