Almost half a dozen aviation businesses have come out in support of the government proposal to invest in Manchester's public transport system in return for a congestion charge.

Manchester Airport, British Airways, Alpha Airports Group, SSP UK Air and VLM Airlines have joined United City, a 107-strong group that supports the Transport Innovation Fund (Tif) bid.

If the Tif bid is implemented, the Metrolink light rail network will be extended to the city's international airport.

Critics point out that the airport lies outside of the two-tier congestion zone.

Manchester Airport managing director Andrew Cornish said: "Improving the way that our passengers and staff access the airport is a key objective of our Master Plan to 2030.

"A successful Tif bid would enable us to reach our targets within the next five years."

Between them, the five aviation companies employ 20 per cent of the total workforce at Manchester Airport.