The comments from Total - the first Western oil company to sign binding agreements to develop Iran's oil and gas fields following the end of a previous round of sanctions in 2015 - illustrate the challenge posed by renewed us restrictions.
Total underscored it would be highly vulnerable to possible U.S. sanctions given that the company has a whopping 10 billion dollars of capital employed in its USA assets, while American banks are involved in 90 percent of Total's financing operations.
Supporters of the deal, which lifted earlier sanctions on the Islamic Republic in exchange for it curbing its nuclear ambitions, need to find a way to reassure companies that their investments are beyond Washington's extra-territorial reach.
Danish oil product shipping operator Maersk Tankers said it would wind down its customer agreements in Iran by November, while German insurer Allianz said on Tuesday it was preparing to wind down Iran-related business.
Total signed a contract in 2017 to develop phase 11 of Iran's South Pars gas field, with an initial planned investment of $ 1bn (£750m).
Against this, Complete mentioned it had spent lower than 40 million euros ($47 million) on the Iranian challenge, which it runs with its associate Petrochina and which is devoted to the provision of home gasoline inside Iran.
European Commissioner for Migration and Home Affairs Dimitris Avramopoulos, for his part, said that the EU is discussing "the possibility of applying our blocking statute" to protect the interests of European companies from the re-introduction of United States anti-Iranian sanctions.
In a deal first signed in late 2016, Total agreed to operate the South Pars project with a stake of 50.1%.
Total said it was working with French authorities towards trying to secure a waiver for the South Pars project.
Iranian oil minister Bijan Zanganeh said the French firm would not pay a penalty if it pulled out of the project.
Companies are starting to take matters into their own hands as European and some other governments struggle to save the Iran deal.
France, Britain and Germany are now in talks with Tehran in a bid to try to salvage the Iran nuclear deal after Washington's withdrawal from the agreement earlier this month. "They have us by the throat because so much business is conducted and cleared in dollars", one European investment banker said. Joe Kaesar, the CEO of Germany's Siemens, told CNN his company would not be able to do any new business with Tehran. "With that in mind it's a logical decision", a European diplomat said of Total's decision.
Should France's Total pull out of the project on development of South Pars gas field's phase 11, China's CNPC will replace it, Zanganeh told reporters on Wednesday.