Bristol Airport reacted to the proposal it should be closed and replaced with a larger airport inside Wales by insisting it is "well positioned to meet the connectivity requirements of both regions in the medium and long term."
"No doubt the Airports Commission will receive many proposals for airport schemes right across the UK. It is important that these are deliverable solutions not somewhat far-fetched proposals reliant on the forced closure of a successful, privately owned airport which supports thousands of jobs."
The Severnside Airport proposal has been submitted to the UK Government's Airports Commission, which is looking into airport capacity around the UK. The commission says it is not responding to individual bits of evidence currently.
Cardiff Airport and Bristol Airport should both close, and be replaced by a new larger 'Severnside Airport' serving south west Britain, according to an influential think tank.
Research published today by the Institute of Welsh Affairs recommends the new airport should be built on the edge of the estuary between Newport and Chepstow, with convenient access to the motorway system and a newly-electrified rail service the key benefits.
The study, carried out by aviation consultants MSP Solutions, supports the Welsh Government's plan to buy Cardiff Airport, but only in the short term.