Air transport hub in west London reports 7.86m passengers in July, compared with 8.15m for Istanbul’s new airport away from the city

Istanbul airport has overtaken Heathrow as Europe’s busiest airport by passenger numbers, leading the London hub to say its “case for expansion has never been clearer”.

Figures published on Tuesday showed 7.9 million passengers passed through Heathrow’s terminals in July, compared with Istanbul’s 8.15 million.

Carriers warn they cannot hold off passing on costs for long, while some airlines plan to increase flights via Asia

• Business live – latest updates

Europe’s biggest airlines have said the rise in fuel prices caused by the war in the Middle East will drive up fares and are advising passengers to book early.

While carriers have partly hedged the price of jet fuel, bosses said they could not avoid passing on additional costs to passengers for long.

Some repatriation flights depart as governments around the world work to extract their citizens from the conflict-hit region

• US-Israel war on Iran – live updates

The biggest Middle East carriers have ruled out resuming scheduled flights until at least Thursday as the US-Israeli war on Iran continues, denting hopes of a swift return to normal air travel after the first repatriation flights left the United Arab Emirates.

Etihad, based in Abu Dhabi, said its commercial services were suspended until 2pm local time on Thursday 5 March, with Emirates ruling out scheduled flights until midnight on Wednesday.