PARIS (Reuters) - Europe must make clear how it will react if the United States pulls out of the multinational nuclear deal with Iran and do more to encourage international banks to return to the country, a senior Iranian official said on Tuesday. Last month, U.S. President Donald Trump broke ranks with European allies, Russia and China by refusing to re-certify Iran s compliance with its 2015 nuclear deal with world powers, reached during Barack Obama s tenure. The Republican president gave Congress 60 days to decide whether to re-impose economic sanctions on Iran, lifted under the pact in exchange for scaling down a program the West fears was aimed at building a nuclear bomb, something Tehran denies. European leaders say they are determined to keep alive the accord which offered Iran an economic lifeline and opened new investment opportunities for European businesses. But the official, who declined to be identified, said Tehran expected Europe to be more proactive in explaining its stance should the United States pull out.  If they want to wait until Trump decides to make a decision it will be too late,  the official said, speaking in English.  For the time being we are hearing from Europe that they want to stick to (the nuclear deal), but if Trump decides otherwise they have no other ammunition.    It is important for European countries to work with Iran,  the officials said, adding that European capitals needed to stick to their commitments  not just in words but in practice .  The official described the lack of big multinational banks returning to Iran as a  deficiency  saying that Europe had committed as part of the deal to normalize business ties with Iran, which he said was still not the case.   When Total comes to Iran to sign an agreement with Iranian entities they do not use French banks. They use others. Why?  The official reiterated that Iran would not be first to leave the deal and accused the Trump White House of deliberately creating uncertainty for foreign firms eyeing new investments in Iran.   We consider the American approach to the JCPOA (nuclear agreement) as dishonest,  the official said in Paris. 