Originally Posted by
Fly.Buy
Yes until 2011, Iran Air Heathrow flights stopped at Manston to refuel thereby circumventing US sanctions.
The circumvention continued for several years after that - after the Manston flights ceased in December 2011, the LHR-IKA flight routed via Vienna for a few weeks, then via Ljubljana or Malpensa for while and more recently via Prague.
It's only since January 2016, when US sanctions were lifted, that they have actually been able to fly direct to Tehran from LHR.