More than two-thirds of MPs from both the Conservative and Labour parties support a third runway at Heathrow, according to a poll.
Survey firm ComRes found that 68% of Tory members and 66% of those representing Labour were in favour of expansion of the west London airport.
Heathrow released the data as it began another year of lobbying for the scheme, which was recommended by the Airports Commission last summer.
The government had been due to decide how best to tackle the air capacity crisis in the South East by the end of 2015, but delayed a decision until this summer.
ComRes asked 150 MPS for their views towards the end of last year.
Almost twice as many MPs said they strongly supported a third runway at Heathrow than a second at Gatwick, according to the poll.
More than eight in 10 said an additional runway in the South East was “necessary for the UK to remain competitive as a centre for international business”.
Heathrow chief executive John Holland-Kaye said: “Heathrow expansion has backing from business groups, trade unions and exporters across the breadth of the UK because it is the only way to connect the nation to the fastest growing economies in the world.
“Expansion will allow Heathrow to be the best connected airport in the world, as well as the most environmentally responsible. As we move in to a new year, this latest polling demonstrates we have majority support from MPs and confirms the breadth of support for Heathrow expansion across the political divide.”
Back in May 2013, the cross-party Commons transport select committee of MPs urged ministers to allow construction of a third runway at Heathrow - and even called for them to consider more radical proposals to build a fourth landing strip.