Qatar Airways will reveal a “very large loss” when it publishes results for the financial year to March, blaming the blockade on Qatar by Saudi Arabia, the UAE and other regional states.

Akbar Al Baker, Qatar Airways chief executive, hit out at the blockade and conceded it had “created problems” for the carrier, but declined to give details of the losses aside from describing them as “very large”.

Saudi Arabia, the UAE and Bahrain severed relations with Qatar in June last year over Qatar’s alleged support for terrorism. Egypt also cut diplomatic ties and Qatar refused to comply with a list of demands

Speaking at German travel trade show ITB in Berlin, Al Baker said the blockade “put a lot of financial strain” on the carrier and “seriously added” to flight times around the world. But he insisted Qatar Airways remains “financially robust”.

Al Baker said: “We have to circumvent the blockaded air space. It has seriously added to flight times to North Africa, to South Africa, to the Indian sub-continent, to the Far East, to China. It makes 15-20 minutes difference to Europe and the US.

“It’s not only extra fuel burn, it is extra maintenance, it affects crew flight times and crew allowances. It also impacts our slot times.”

Yet he insisted: “People still prefer to travel on Qatar Airways.”

The carrier has a global network connecting 150 destinations through its hub at Doha and depends on the resulting long-haul traffic, much of it between Europe and the rest of the world.

Al Baker said: “We don’t know how long the blockade will last. We expect it to continue. I think it will be long term.”

However, he said: “During the blockade Qatar Airways continued its expansion. We kept our country supplied and we became prouder as a nation.

“We are more independent than we were nine months ago. We are defiant, and Qatar Airways will keep on expanding.”