Turkish Airlines is to introduce a fourth seating class on its Boeing 777 aircraft

The has designated the service 'Comfort Class', essentially a premium-economy cabin which will be brought in to complement its standard three-class product.

Turkish Airlines said the purpose is to combine the convenience of business-class with the reasonable purchasing rates of economy-class.   Seats will be pitched at 46in (116cm) and feature in-arm 10.6in video screens.

The airline will initially offer the product on its Beijing , Shanghai , Tokyo and Bangkok routes, as well as services to Sao Paulo and Toronto .

It says it also plans to provide the four-class seating on new 777s which will be used on the New York , Chicago and Washington routes, depending on delivery time.