"That's why we, Britain, France, Germany but also the members of the European Union, believe it's not right to cancel this agreement in this situation now", said Merkel, adding that concerns about Iran's ballistic missile program and its destabilizing influence in the region could best be discussed with Tehran by preserving the deal.
Mogherini says "there was awareness of the urgency" and the four ministers agreed to find some solutions within weeks.
German Chancellor Angela Merkel pushed back on Wednesday against Washington's rejection of the Iran nuclear deal, saying the accord helped outside powers anxious about Tehran's regional role to pursue their concerns with the Islamic Republic.
German officials said Tuesday they plan to increase defense spending this year, but not to levels high enough to meet President Donald Trump's demands.
The president, who participates in the sessions of the Bundestag for the approval of the 2018 federal budget, said in relation to the JCPOA that 'the question is whether it is convenient to end the agreement or maintain it, and we consider it better to remain in it'.
President Donald Trump announced last week the US would pull out of the 2015 accord, which is created to keep Tehran's nuclear ambitions in check and took over a decade to negotiate.
Merkel said the Europeans aren't "blind" to threats posed by Iran's activities in Syria to Israel, for example.
The statement came a week after President Donald Trump announced that the United States would withdraw from the JCPOA despite the fact that Iran remained in compliance with the deal as verified by the IAEA in 11 inspection reports.
At meetings with Iranian Foreign Minister Mohammad Javad Zarif in Brussels on May 15, the European signatories vowed to keep the JCPOA alive despite the USA withdrawal.
The EU hopes to convince Iran to continue to respect the landmark nuclear pact.