British Airways is suspending its flights between London and Iran because they are “not commercially viable”.
The airline announced it will stop flying between Heathrow and Tehran next month.
It apologised for the disruption to passengers due to travel on later flights and is offering refunds or the option to bring their itineraries forward.
A number of foreign companies have announced plans to pull out of Iran since US president Donald Trump withdrew from the nuclear deal with the Middle Eastern country and reinstated sanctions.
He has accused Iran of supporting terrorism and undermining global financial systems.
In August 2015, the British embassy in Tehran reopened after it was ransacked by a mob in 2011.
British Airways resumed London-Tehran flights after a gap of four years in September 2016. The service was suspended in October 2012 amid instability in Iran.
It currently operates five flights per week in each direction. The last outbound flight to Tehran will be on September 22, with the final inbound flight to London on the following day.
A spokesman for the carrier said: “We are suspending our London to Tehran service as the operation is currently not commercially viable.
“We are sorry for any disruption this may cause to our customers’ travel plans and we are in discussions with our partner airlines to offer customers rebooking options.
“Alternatively, they will be offered a full refund or the opportunity to bring their flights forward.”
Dutch carrier KLM announced last month that it will also suspend its Tehran flights in September due to “negative results and financial outlook”.