International investors in the airport will fund plans to ramp up spending to pave the way for expansion of Terminal 2 and a new access tunnel.

The plans send a strong signal that Britain continues to be open for business in the eyes of international investors.

With the UK set to leave the European Union in 2019, the planned investment aims to further boost passenger experience at the UK’s hub airport and improve Heathrow’s operational resilience.

Initial plans for the new investment include the possibility of enabling works for the expansion of the award-winning Terminal 2 and planning works for a new southern access tunnel for road traffic to the Central Terminal Area.

The details of those projects will now be worked on by Heathrow and presented to the airport’s shareholders for approval.

Heathrow’s international shareholders include Ferrovial, Qatar Investment Authority, Caisse de dépôt et placement du Québec, GIC, Alinda Capital Partners of the United States and China Investment Corporation.

Chief of the Qatar Investment Authority, Sheikh Abdulla Bin Mohammed Bin Saud Al-Thani,  said: “Our investment in Heathrow is much more than just an investment in one of the world’s great airports – it’s an investment in Britain’s connections to the world.

“As the UK reshapes its role in the world, we confirm our commitment as proud partners of a great trading nation.”

Heathrow CEO John Holland-Kaye said: “The planned investment is great news for Heathrow passengers and for Britain – it will help us build on our success as passengers’ Best Airport in Western Europe and further improve resilience at the nation’s hub.”