London City Airport and the Met Police should carry out a full perimeter seurity review in the wake of the September 6 incursion by the Black Lives Matter group which closed the airport for several hours.

This is the recommendation of Lord Toby Harris, who carried out an independent review of London’s preparedness for terror , published before the recent CS gas spray incident that also shut down the airport terminal.

Lord Harris said he had been “broadly reassured by the policing presence and plans in place” at London’s airports but the BLM invasion “does raise serious questions about the perimeter security and access from the river”.

A police dinghy sails past as planes stand after a protest closed the runway causing flights to be delayed

He added: “It is important we are not complacent about the protection offered by our border, particularly in London where St Pancras International, Heathrow and London City Airports, and the River Thames bring that border directly into the capital.”

He highlighted the Thames as a particular security weak spot with a number of agencies involved in its monitoring but requiring, he said “a stricter regime”. He recommended the Port Of London Authority had a wider remit to include security and a separate review to be undertaken next year.

The emergency services are seen outside London City Airport

Lord Harris made 127 recommendations in all including direct messaging to Londoners in the event of a major terrorist attack; increased CCTV on public transport; and greater use of temporary barriers to prevent a Nice style attack.

Lord Harris said: “The quality and effectiveness of the work done by the intelligence services and the counter-terrorist police is among the best in the world, and if London were subject to a terrorist attack today, our emergency services response would be substantially faster than five years ago.

“Nevertheless, a serious terrorist attack remains highly possible and we cannot be complacent.”

Referring to the discovery of a “viable” device on a Tube train in North Greenwich last month , Mayor of London Sadiq Khan said: “[These] events remind us what a fantastic job our police officers and emergency services do every day to keep us safe. But there is more that can be done by a wide range of organisations, and Lord Harris’s many recommendations deserve careful consideration.”