The Government must look beyond a third runway at Heathrow to achieve necessary airport capacity, engineering and transport experts have said.
The aviation debate had become too heavily politicised, said the Institution of Civil Engineers (ICE) and the Chartered Institution of Highways and Transportation (CIHT).
They said the long-term choice was not whether to build a third runway at Heathrow but whether the west London airport could realistically be expanded beyond three runways. If not, plans for an alternative hub airport in south-east England must be developed quickly. The two organisations were responding to the Government's draft aviation policy framework.
The ICE and the CIHT also made mention of the Government-appointed Commission into aviation needs headed by former Financial Services Authority chief Sir Howard Davies.
The institutions called for a "twin track" approach to aviation capacity, which pushes ahead with solutions that will maintain the UK's position as a leading aviation hub in the longer term.
The approach should also focus on what can be delivered in the short term to help relieve the capacity restraints at Heathrow and keep the UK from slipping even further behind its European rivals. They said the approach should acknowledge the crucial role UK regional airports play through connecting flights to the national hub and ensure regional airports' ability to fulfil this role is not undermined by lack of access to landing slots at Heathrow.
Alex Lake, from ICE's aviation expert panel, said: "Looking to the longer term, to maintain its global economic competitiveness, the UK needs a hub with more than three runways and rapid access to central London. If we decide Heathrow can't or shouldn't be expanded to this size we will need to develop a new hub facility elsewhere in south east England. This will naturally take time, so the Davies Commission must press on with evaluating all available long-term options now."
CIHT chief executive Sue Percy said: "The creation of the (Davies) Commission is welcome, but its final report will not be published until after the 2015 General Election, potentially causing yet more delay and indecision and damaging the UK's credibility as a location for private investment in aviation infrastructure.
"The Commission's interim report in 2013 must indicate a clear direction of travel and come 2015, Government should make an unambiguous decision that has cross-party consensus and can be driven forward."
A Department for Transport spokesman said: "The strength with which the different options are put forward shows precisely why we were right to set up a proper independent review with the timescale to consider fully what is in the country's interest. Maintaining the UK's status as a leading aviation hub is vital to our economy and history suggests that, without an agreed evidence base and a high degree of political consensus, it will not be possible to deliver a lasting solution that is right for the UK."