Theresa May is being urged by 50 politicians to give the OK to a new runway at Heathrow.
The group, from across the UK, said Heathrow was ‘our gateway to the world’.
In a letter, the politicians said: "Although Heathrow is in London, it is the UK’s hub airport.
"Other countries are investing in and supporting their hub, or looking on enviously as they hub through other countries.
"Northern Ireland, Scotland and Wales all have our own successful and growing airports.
"But Heathrow is our gateway to the world, bringing tourists to our attractions and helping our exporters reach new markets.
"Whether we are connected by road, rail or air, we know that connections to Heathrow are a key driver of investment decisions.
"Expanding Heathrow will create nearly four times more jobs in our three nations than other options being considered."
A cabinet sub-committee is due to meet to examine the arguments for the three options set out in last year’s Airports Commission report.
The commission recommended in July 2015 that a third runway should be built at Heathrow.
It had been thought an announcement could be made as early as this week, but some insiders say the decision will be delayed until the Witney by-election.
