April schedules data from FlightGlobal shows that 75 airline services will be covered by new UK restrictions on the size of electronic devices that can be taken as hand luggage, around two-thirds of them on Turkish routes.

The UK on 21 March adopted new security measures under which phones, laptops and tablets with dimensions exceeding 16cm by 9.3cm by 1.5cm will not be allowed in the cabin on flights to the country from Egypt, Jordan, Lebanon, Saudi Arabia, Tunisia and Turkey.

Similar restrictions has been imposed by US authorities on 20 March, covering 10 airports. Five of these airports –Istanbul Ataturk, Cairo, Amman, Jeddah and Riyadh – are in countries to which the UK restrictions apply, and there are no direct services to the USA from other points in those countries. The UK has not applied its measures to Kuwait, Morocco, Qatar and the UAE – the other countries with airports covered by the US restrictions.

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FlightGlobal schedules data for April shows more than 1,400 scheduled flights from these six countries into the UK. These account for almost 300,000 seats across the month, an average of around 10,000 seats a day. There are spread across 75 scheduled airline services.

Turkey to the UK is the biggest of the markets covered by the UK's new restrictions. There are 49 services operated by nine airlines scheduled for April, spread across 34 routes. Scheduled Turkish capacity is slightly higher in this year's peak summer months than in April.

Turkish Airlineshas the most capacity into the UK from Turkey. It has more than 80,000 seats scheduled into the UK market during April, across six different routes. The largest of these is Istanbul Ataturk-LondonHeathrow.

While the routes covered by the US restrictions are only operated by overseas carriers, the UK restrictions apply to several home operators.British Airwaysserves five of the countries covered – its flights on the routes in question accounting for around 40,000 seats in April. Tunisia is the only one of the six countries that BA does not serve.

In imposing the restrictions, the UK said it faced a "constantly evolving threat" from terrorism and that the government "must respond accordingly" to ensure the protection of the public. But it stresses that it is "not currently advising against flying to and from those countries" affected by the measures.