The European Union will work to protect its strategic and economic interests in Iran after the US withdrawal from the international nuclear deal, the bloc's foreign policy chief said on Monday.
Federica Mogherini said after a meeting of EU foreign ministers that member states were closely co-ordinating their efforts "to protect the economic investments of European businesses that have legitimately invested and engaged in Iran" over the past three years since the nuclear deal was agreed.
President Donald Trump pulled the US out of the pact this month and wants to impose tough sanctions on Iran, which might affect some European companies doing business with Tehran.
European powers say they are committed to keep working together to save the deal because they believe it is the best way to keep Tehran from developing a nuclear bomb.
Ms Mogherini insisted the EU was not motivated by business profits in trying to keep the deal alive.
"For us, this is not about an economic interest. It is about a security interest," she said.
She also downplayed reports of friction between Poland and the rest of the EU over how to deal with Mr Trump's hardline stance toward Tehran.
Ms Mogherini said the EU as a whole shared some of Mr Trump's concerns over Iran's role in the Middle East and its ballistic missile programme.
Overall though, she said, "the first concern we share is one related to the possibility for Iran to develop a nuclear weapon" and sticking to the nuclear deal was the best way to prevent that.
However, Polish Foreign Minister Jacek Czaputowicz said his country opposed any EU actions that would weaken US sanctions and that encouraging the continued operation of European companies in Iran could become a big problem.
He said that those "states that tie their security to United States security" shared views similar to Poland's given their interest in preserving their transatlantic relationship.
Mr Czaputowicz also called for a compensation mechanism if European companies operating in Iran were to suffer losses.
The EU's executive commission announced last week that it would start revising a so-called blocking regulation that was drawn up in 1996 in response to the fallout from US sanctions on Cuba, and on Libya and Iran.
The measure has never been used, but in essence it bans companies from respecting American sanctions where those sanctions might damage EU interests, notably trade and the movement of capital.
For the blocking regulation to be used now, it would have to be updated to include US nuclear-related sanctions against Iran. This would take time and runs the risk that any one of the 28 EU member countries could block the move.
The EU is also ready to allow the European Investment Bank to help companies invest in Iran. On top of that, the EU's energy commissioner is heading to Tehran for talks on boosting energy co-operation.