An aviation chief has blasted May and Trump's laptop ban as ineffective
Alexandre de Juniac, chief executive of the International Air Transport Association said the measures are “not acceptable” for long-term use.
Under the new measures, devices larger than a cellphone, including laptops and tablets, must be stowed with checked baggage.
The ban will promote a future of “restricted borders and protectionism”, the chief claimed.
Announced last week, the restrictions apply to direct flights to Britain and the US from certain airports in the Middle East, North Africa and Turkey.
Theresa May has banned electric devices on inbound direct flights from Turkey, Lebanon, Jordan, Egypt, Tunisia and Saudi Arabia, while the US electronics ban affects nine airlines flying from 10 specific airports in Jordan, Egypt, Turkey, Saudi Arabia, Kuwait, Morocco, Qatar and the United Arab Emirates.
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Prime Minister Theresa May has promised to 'build a greater Britain'
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Theresa May in the cabinet, sitting below a painting of Britain's first PM Robert Walpole, signs the official letter to European Council President Donald Tusk invoking Article 50 and the United Kingdom's intention to leave the EU on March 28, 2017
In a damning speech to the Montreal Council on Foreign Relations, Mr de Juniac questioned the measures. He said: "Why don't the US and the UK have a common list of airports?
“How can laptops be secure in the cabin on some flights and not others… especially on flights originating at a common airport?"
He added: “The current measures are not an acceptable long-term solution to whatever threat they are trying to mitigate.
“Even in the short term it is difficult to understand their effectiveness. And the commercial distortions they create are severe."
President Trump’s regulations were prompted by reports that militant groups want to smuggle explosive devices onto flights in electronic gadgets.
Britain followed suit with a similar ban on larger carry-on electronics on direct flights from six countries. France and Canada said last week that they were examining their own policies.
Alexandre de Juniac said the laptop ban would restrict borders
A US security official told Reuters on Tuesday that the electronics restrictions were a "calculated move" based on reliable intelligence.
The official insisted Trump's administration would stick with the policy.