London's Heathrow Airport will submit its proposal for a third runway this summer, the chief executive of the hub said, weeks after the British government threw its weight behind the project citing its potential to boost trade and economic growth.

U.K. Treasury chief Rachel Reeves says that the new Labour government is backing the construction of third runway at London’s Heathrow Airport.

The line, called the Heathrow Southern Railway (HSR), is a privately financed proposal to link Surrey towns to one of the world's busiest airports. If built, it would operate between Heathrow and London Waterloo via Staines.

London's Heathrow Airport, one of the world's busiest hubs, will submit its proposal for a third runway to the British government by summer, its chief executive Thomas Woldbye will say in a speech on Wednesday.