British Airways said in a statement that it had decided to suspend its flights between London and Tehran from the end of September, as they were "not commercially viable" at the time.
Air France, questioned by AFP, said it decided to end its ties with Tehran from 18 September because of their low commercial profitability.
The company, which had switched to Joon, its low-cost airline, its links with Tehran, "has gone from three weekly frequencies to one since August 4 and stops the connections with Tehran on September 18 because of the low commercial profitability" of the line, according to the communication department of the group.
Air France had resumed flights to Tehran in April 2016 after it had hanged them in 2008 after international sanctions against Iran.
The last flight from British Airways to Tehran takes place on September 22 and that of the Iranian capital on the 23rd.
This company resumed its direct flights to Iran two years ago, against the background of a major international agreement on Iranian nuclear power and the lifting of sanctions.
Other European airlines operate Iran, such as Lufthansa or Alitalia.
The Dutch company KLM had already announced at the beginning of July that they would suspend the flights between Amsterdam and Tehran from 24 September, also mentioning "commercial reasons".
What is the beginning?
The airlines offer their customers who already have reservations for Tehran flights with partner companies, a refund, a voucher or the possibility to make the trip.
US President Donald Trump announced on 8 May the withdrawal of the United States from the nuclear treaty signed in 2015 between Iran and the major international powers.
This agreement, concluded after two years of negotiations between Iran, the United States, China, Russia, Great Britain, France and Germany, has made it possible to lift sanctions in exchange for Iran's commitment not to acquire nuclear weapons.
The withdrawal of the US from the 2015 agreement and the unilateral reinstatement of strict sanctions against Tehran endanger the activities of European multinationals in Iran.
"Anyone doing business with Iran will NOT do business with the United States," threatened Prime Minister Trump in early August, after Israeli Prime Minister Benjamin Netanyahu, who continues to condemn the nuclear deal with Iran. and calls for sanctions against Tehran.
"Today we have heard that three airlines – BA, KLM and Air France – would end their activities in Iran, which is good news," said Netanyahu, who arrived in Lithuania on Thursday to rebalance, "not always friendly relations" between Israel and the European Union.
"But more can be done and more will be done, because Iran should not be rewarded for its aggression in the region and its efforts to spread terrorism," he added.
The sectors of car industry, aerospace, oil industry, railway industry and shipping, tourism, pharmaceuticals and the banking sector are particularly exposed to US sanctions.
Daimler, the world leader in high-end cars and trucks, has thrown the towel into the ring, while the French PSA (Peugeot, Citroën …) is preparing to suspend its activities.
The French industrial gas group Air Liquide has ceased its commercial activities in the country, while the French oil giant Total has officially withdrawn from its investment projects with a value of several billion dollars.
In July, the United States rejected the European requirements not to punish companies that operate in Iran because they do not want to encourage trade with Tehran.