Egyptian airlines were ordered to avoid Iranian airspace for three hours on Thursday after a notice from Tehran to do so because of military drills, according to Egypt’s Civil Aviation Ministry. 

The warning came amid skyrocketing regional tensions following the assassination of Hamas’ leader in Tehran last week. 

Egypt said the caution came in the form of a notice sent by Iran to all commercial airlines. 

The ban from Iranian airspace will reportedly last for three hours – from 4:30 am to 7:30 am on Thursday. Iran’s warning also covered three hours earlier on Wednesday, the Egyptian ministry added. 

Speaking to Iran’s ISNA news agency, the head of the Iranian international airport in the capital city of Tehran Saeed Chalandari denied reports of a warning against entering western Iranian airspace, though it was not clear whether that applied to the entire country. 

Israel has been bracing for an attack by Iran and its allied militias over the assassinations in Tehran of Hamas’ top leader Ismail Haniyeh, as well as the assassination of a senior Hezbollah commander in Beirut. 

Both Iran and Hamas blamed Israel for the explosion that killed Haniyeh, but Israel has neither confirmed nor denied responsibility.