By Anthony O. Goriainoff

London's Heathrow Airport said on Thursday that passenger numbers in October grew to 3 million as the relaxation of travel rules unleashed pent-up demand.

The airport--jointly owned by the Qatar Investment Authority, China Investment Corp., Spain's Ferrovial SA, and other investment companies--said that despite clear signs of recovery, and October being the six month of consecutive growth, passenger levels remained 56% below pre-pandemic levels.

"With air travel at other major European airports recovering faster, ministers should reassess testing requirements for fully vaccinated passengers and the Passenger Locator Form at the next Global Travel Taskforce review, to ensure the U.K. is aligned with its European competitors," the company said.

The company also said that its ability to support the elements of the U.K.'s economic recovery which will be driven by an increase in international air travel and trade, depends on the Civil Aviation Authority's next regulatory outcome.

In October the CAA published a consultation on its initial proposals for the next price control period at Heathrow.

"To deliver the safe, resilient and sustainable airport passengers and exporters need, the regulator must ensure the settlement reflects the size of the asset and costs required to run and invest in it," the company said.

Write to Anthony O. Goriainoff at anthony.orunagoriainoff@dowjones.com