France has called on French visitors "currently in Iran" to “leave the country as soon as possible" due to the "increased risk" of military escalation between Israel and Tehran following the killing of a Hamas leader in Iran attributed to Israel.

The French Foreign Ministry, which did not specify the number of French nationals potentially affected by this new recommendation, pointed out that all Iranian territory is marked in red on the travel advisory map.

"French citizens are therefore officially advised not to travel to Iran for whatever reason," the ministry said.

Ismail Haniyeh, the political leader of the Palestinian Islamist movement, was assassinated in Tehran on Wednesday. A few hours before this attack, Fuad Shukr, a military commander of the Lebanese Islamist movement Hezbollah, was killed in the southern suburbs of Beirut on Tuesday.

The two attacks have rekindled fears that the war between Israel, on the one hand, and Iran, on the other, and the groups it supports in Lebanon, Syria, Iraq and Yemen, is spreading throughout the Middle East.

"Given the growing risk of military escalation in the region, French citizens currently in Iran are invited to leave the country as soon as possible," the French Foreign Ministry appealed.

The ministry also asked French citizens to "exercise the utmost caution, stay away from all demonstrations, stay informed of the situation and regularly consult the embassy website."