Bristol International Airport bosses are being urged to listen to concerns raised over its expansion plans.

Both Weston MP John Penrose and Dr Liam Fox, whose Woodspring constituency includes the airport, believe expansion will create additional jobs and travel opportunities.

But both fear local residents will suffer and have submitted a joint letter to the airport's chief executive Robert Sinclair highlighting their concerns.

These include the effect on transport links from an increase in passenger numbers and more disturbance for families.

The MPs claim there seemed to be no plans to address the increase in flight noise or to reduce congestion on roads to and from the airport.

A Bristol Flyer coach service already operates between Bristol city centre and the airport but the MPs said there was no prospect of it being extended to cover journeys between Weston and the airport or Bath.

Mr Penrose and Dr Fox also claim the airport wants to increase car parking on green belt land.

A consultation over the airport's growth in the future has been running since January and will end tomorrow.

The aim is to discover peoples' views on the plans before an application is submitted to North Somerset Council.

The letter from the MPs states: "Our biggest objection, however, is the impact that a large increase in passenger numbers will have on our already over-stretched transport infrastructure.

"If passengers were only coming from the centre of Bristol then an increased frequency of public transport might be an answer but the truth is that a huge amount of traffic makes its way up the A38 from the South or across from the M5 via Junctions 19, 20 and 21.

"There is nothing in the current planned infrastructure that would help alleviate this problem.

"The plan to convert part of the current car park by the terminal into a discrete underground multi-storey is welcome but there is no evidence to suggest that a large increase in ground level parking, on what is currently green belt land, is justified.

"It is also difficult to believe that in the current appalling economic climate, passenger numbers are likely to rise in line with previous estimates, if at all.

"We would urge you to look again at the entire economic case for expansion of the airport in the timescale envisaged as many of the assumptions of a growing economy might not be replicated in a recession.

"The bottom line is that many of our constituents would be asked to pay the environmental cost of airport expansion without seeing significant benefits."

Susan Pearson, of Stop Bristol Airport Expansion (SBAE) said: "We are expecting the airport to put in a major planning application for a bigger terminal and more parking, which is what they need to bring passenger numbers to 10 million by 2016.

"That planning application will have a three-week public consultation period and from our point of view it is important the public know about this.

"The airport has said the expansion will create 4,000 jobs, we think this is fantasy as they have provided nothing to back up this claim.

"They will have to include a proper report to show how they reached those figures with their planning application.

"Our other problem is surface access as by 2016 there will still be 85 per cent of passengers arriving by car and 15 by public transport.

"This is a hell of a lot more cars on the roads," she said.

"New bus services from towns such as Weston are something we would welcome but this is something we want to see written in black and white.

"Our other concern is about noise as a wider airspace will be used with increased flights."

Airport boss, Mr Sinclair said: "First of all we are disappointed with this response by the MP's but the important thing to note is we have not submitted the planning application yet, we are still in the process of completing the consultation.

"This is a process whereby we have been out consulting with the community to understand the issues the local community has with the development proposals.

"Our current plans have already taken into account issues raised in the early planning process.

"There are one or two issues we need to address such as noise and transport.

"We are seriously looking at buses travelling to the airport from other towns and as part of the planning application we are looking to commence services such as buses from Weston-super-Mare. We are very much listening to the community.

"This is an opportunity to develop Bristol in a way which is sustainable and takes the interests into account of residents' who live close to the airport.

"I think it is premature for the MPs to form a final view with a development proposal before it is final.

"I think it is important to say Bristol airport is already constrained and suffers congestion in terms of car parking spaces, number of gates, aircraft stands.

"We believe therefore it is essential for the airport to enhance its services already provided to customers.

"We are looking at multi-level car parks, covered access, air bridges so passengers can walk directly onto aircraft; these are the sorts of things the travelling public ought to expect.

"We expect growth to continue and this is a long term development over eight-10-years.

"It will be a move creating more than 4,000 jobs including ground handlers, caters, car park attendants, firemen and security personnel.

"We are also very focused on enhancing the growth of inbound tourism. Fifteen per cent of passengers are inbound at the moment but we see that increasing especially with the level of the pound."