The European Union's efforts to protect Iran's benefits from the 2015 nuclear deal after the U.S. pull-out are not enough, Iranian Foreign Minister Mohammad Javad Zarif said Sunday.

"With the withdrawal of America... the European political support for the accord is not sufficient," Zarif told Miguel Arias Canete, EU commissioner for energy and climate, during a meeting in Tehran.

European leaders have been scrambling to save the deal after the Donald Trump administration announced its withdrawal on May 8. Formally known as the Joint Comprehensive Plan of Action (JCPOA), the agreement was additionally signed by France, Germany, the U.K., Russia and China and lifted most economic sanctions on Iran in exchange for restrictions to its nuclear program.

Despite the signatories' broad disagreement with the White House's decision, and pledges to continue upholding the deal that they argue has worked in containing Tehran's nuclear activities, the imposition of sweeping U.S. sanctions makes this a challenging and unlikely feat. The U.S. Treasury is set to re-impose prior sanctions after a 90 or 180-day wind-down period, dependent on the sector, with particularly significant sanctions targeting Iran's oil industry and transactions with its central bank.

European companies with significant investments or plans in Iran have now suggesting withdrawing for fear of facing U.S. penalties, including French oil giant Total and auto manufacturer Peugeot, who have said they will pull their activities from the country if they cannot obtain U.S. sanctions waivers.

"The announcement of the possible withdrawal by major European companies from their cooperation with Iran is not consistent with the European Union's commitment to implementing (the nuclear deal)," Zarif was quoted as saying Sunday.