The UK's next government must commit to at least two new runways after the election, the Institute of Directors has demanded.
MPs will vote on expanding Heathrow later this year, but the IoD has called for dramatic action to prevent the UK's airport capacity falling behind.
It is the second call for more airport tarmac within days. Last week, the London Chamber of Commerce and Industry also called on ministers to back a new runway at Gatwick.
The runway call is the latest in a series of demands from the IoD, which has also urged greater power for shareholders to block executive bonuses and increased support for startups.
IoD senior infrastructure adviser Dan Lewis said: “Whoever wins the next election, they will face a serious challenge in upgrading the UK's transport and communications network.
“The years of dawdling on new airport capacity have left us lagging well behind European competitors. Expanding Heathrow is not enough, we need two further runways at South East airports and better connections to the ones where there is spare capacity, particularly Stansted.”
In addition to more aviation capacity, it is also asking for a commitment to upgrading the UK's broadband infrastructure and more detailed plans for Crossrail 2.