The UK and US ban on laptops and tablets in cabin baggage on certain inbound flights has been condemned by a global aviation leader.
Alexandre de Juniac, director-general of airline trade body Iata, claimed the new rules are "not an acceptable long-term solution to whatever threat they are trying to mitigate".
It was announced last week that passengers will no longer be able to carry large electronic devices on flights to the UK from Turkey, Lebanon, Jordan, Egypt, Tunisia and Saudi Arabia.
This will theoretically stop a terrorist on an affected flight from physically triggering a bomb concealed in a laptop and would ensure any explosion takes place in the hold, away from other passengers.
Transport Secretary Chris Grayling said the ban - announced hours after a similar measure by the US authorities - was introduced "in response to an evolving security threat".
In a speech to Canada's Montreal Council on Foreign Relations, Mr de Juniac cast doubt on the value of the regulations.
He said: "Even in the short term it is difficult to understand their effectiveness. And the commercial distortions they create are severe.
"We call on governments to work with the industry to find a way to keep flying secure without separating passengers from their personal electronics."
Mr de Juniac noted that the UK has not included four countries in its ban - Morocco, Kuwait, Qatar and the United Arab Emirates - which are covered by the US.
He told the audience: "With the measures now in place, our passengers and member airlines are asking valid questions. 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, including flights departing from the same airport? And surely there must be a way to screen electronic equipment effectively?
"The current situation is not acceptable and will not maintain the all-important confidence of the industry or of travellers. We must find a better way. And governments must act quickly."
UK airlines operating direct flights which are being hit by the new measures are British Airways, easyJet, Jet2.com, Monarch, Thomas Cook and Thomson.
Overseas airlines affected are Turkish Airlines, Pegasus Airways, AtlasGlobal Airlines, Middle East Airlines, EgyptAir, Royal Jordanian, Tunis Air and Saudia.
The restrictions include any electronic device measuring 16cm (6.3in) by 9.3cm (3.7in) by 1.5cm (0.6in), which means anything larger than a typical smartphone will have to go in hold luggage.
A number of peripheral devices designed to be used with either a phone, laptop or tablet and exceeding the same dimensions are also banned from the cabin.
This covers spare batteries, portable power sources, keyboards, power cable transformers and external hard drives.
This means spare batteries and portable power sources cannot be transported on affected flights in any way, as there was already a ban on them being stored in hold baggage because of a potential fire risk.