A Ukrainian Boeing-737 with more than 170 people on board has crashed in Iran, officials say. Iran's Red Crescent said there was no chance of finding survivors. The Ukraine International Airlines plane crashed just after take-off from Iran's Imam Khomeini airport in Tehran, said the Fars state news agency. The plane was flying to the Ukrainian capital Kyiv. Ukraine's government said a crisis group was being set up to investigate the crash. President Volodymyr Zelensky was cutting short a trip to Oman and returning to Kyiv, a statement said. "My sincere condolences to the relatives and friends of all passengers and crew," he said in a statement. It is unclear whether the incident is linked to the Iran-US confrontation. Rescue teams have been sent to the crash site but the head of Iran's Red Crescent told state media that it was "impossible" for anyone to have survived the crash. Some 168 passengers and nine crew members were confirmed to have been registered to fly on the aircraft, Prime Minister Oleksiy Honcharuk said.