"International companies with interests in many countries make their own choices according to their own interests". The 2015 nuclear agreement is a crucial element of peace and security in the region.
Tehran expressed his opposition to Trump's move, as well as German Chancellor Angela Merkel and her French counterpart Emmanuel Macron expressed concerns over Washington's decision. The US Treasury Department said it would give European businesses six months to wind up their investments in the country or risk US sanctions - forbidding them from signing new contracts.
"But what is important is that companies and especially medium-sized companies which are perhaps less exposed to other markets, American or others, can make this choice freely".
Total on Wednesday said it might quit a multi-billion-dollar gas project unless it secured a waiver from US sanctions.
"Everyone in the European Union shares the view that the agreement is not ideal, but that we should remain in this agreement and conduct further negotiations with Iran on the basis of other issues such as the ballistic missile program", Merkel said as she arrived for the summit.
The summit also comes at a time Facebook is under pressure in the United States and Europe over data privacy after it emerged tens of millions of users' personal data was harvested from the site by political consultancy Cambridge Analytica.
The United States will re-establish sanctions against Iran progressively, kicking off with the automobile and civil aviation sectors, a source close to the French government said on Tuesday.
But while voicing understanding for big companies anxious to protect their U.S. sales, he added that the European Union must stand by smaller companies which were willing to carry on Iran business.