British Airways has been branded the least efficient carrier on transatlantic routes in a study of 20 carriers.

Norwegian was ranked first in overall fuel efficiency among transatlantic carriers due to its use of new Boeing 787 Dreamliners on long-haul services.

Virgin Atlantic and Aeroflot were highlighted as “major improvers” between 2014 and 2017.

This was due to the increased use of more fuel efficient aircraft – the Boeing 787-9 for Virgin Atlantic and Boeing 777-300ER for Aeroflot.

A study by the International Council on Clean Transportation placed BA bottom out of 20 leading airlines, finding that the carrier burnt more fuel per passenger than any of its rivals.

BA burnt 63% more fuel on average last year than Norwegian.

The UK carrier was ranked as the least fuel efficient, falling 22% below the industry average on routes between Europe and North America.

“The fuel efficiency of the least efficient carrier, British Airways, worsened by 4% compared to its 2014 ranking,” the ICCT research found.

The second most efficient airline was Icelandic budget carrier Wow Air, followed by Swiss, KLM, Turkish Airlines, Air France, Thomas Cook and Virgin Atlantic.

“The importance of seating density as a driver of fuel efficiency has increased since 2014 due to the expansion of low-cost carriers which operate transatlantic flights with higher seat counts and a lower percentage of premium seats compared to competitors,” the report said.

The ICCT’s Brandon Graver, lead author of the study, said: “One of the biggest changes in the transatlantic market between 2014 and 2017 was an increase in operations from European low-cost carriers and the further utilisation of newer, fuel-efficient aircraft.

“Airlines like Norwegian, which invests in new, fuel-efficient aircraft, and carriers like Wow Air and Swiss that maximise payload on a given flight, all flew efficiently in 2017.”

A BA spokesman said that the airline had a “greater share of the premium market on the North Atlantic” than other airlines.

Also, the number of first and business class seats on each aircraft was “the main reason its fuel efficiency per passenger appears lower”.

He added: “We are committed to reducing our carbon emissions and have improved efficiency by more than 10% since 2008.

“We are investing heavily in modern, fuel-efficient aircraft, including the 787, A380 and A350, and by 2020 will have received more than 100 new aircraft in a decade.

“We are well on course to deliver a 25% improvement in carbon emissions reduction by 2025.”

Norwegian chief executive, Bjorn Kjos, said: “The most important thing that an airline can do for the environment is to invest in newer aircraft which use the latest technology to be as fuel efficient as possible.

“Our strategy to have a modern fleet is paying dividends not only for our business and customers, but also our planet.”

Dan Rutherford, ICCT’s aviation programme director and report co-author, said: “New policies to accelerate investments in more fuel-efficient aircraft and operations are critical if industry is to meet its long-term climate goals.

“Efficiency improvements today continue to be outstripped by more travellers taking to the sky.”

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