New figures from Heathrow have revealed passenger numbers remained 71 per cent down in August versus the same month pre-pandemic.
The airport said ever-changing restrictions, expensive and unnecessary testing requirements and lack of a common approach across borders were behind the slump.
From being the busiest airport in Europe in 2019, Heathrow is now tenth as rivals including Schiphol, Paris and Frankfurt are all recovering at a much quicker pace.
In response, the airport urged ministers to streamline the system to get travel levels and the economic activity safely back to pre-pandemic levels.
Otherwise, officials argued, the UK will continue to lose trade and face lower levels of foreign tourism, impacting jobs and slowing the economic recovery.
The airport called on the government to remove the amber list and create a safe but simple two-tier system – a green list and red list, retaining hotel quarantine.
Fully vaccinated travellers should not be required to take a test, while those who are not vaccinated should continue to take a pre-departure and arrival test using lateral flow, following up with a PCR test if positive, the airport said.
As passenger numbers grow, Border Force must ensure they have adequate resources and processes in place to ensure travellers receive a warm welcome into the UK.
Recent scenes of passengers waiting for hours to be processed through the UK border are “totally unacceptable,” a statement added.
Heathrow chief executive, John Holland-Kaye, said: “The government has the tools to protect the international competitiveness which will boost the economic recovery and achieve its Global Britain ambitions.
“If ministers fail to take this opportunity to streamline the travel rules then the UK will fall further behind as trade and tourists will increasingly by-pass the UK.”