“The termination of the Iran agreement by the US doesn’t benefit global peace,” he told the Hannoversche Allgemeine newspaper.
“As co-architects of the Iran deal, we must defend its core,” he said.
He said the 2015 pact should not be sacrificed for the sake of US domestic political expediency.
“The Middle East is on the cusp of great turmoil, and we are close,” he cautioned.
The agreement, officially called the Joint Comprehensive Plan of Action (JCPOA), was negotiated by UN Security Council permanent member states – Russia, China, the United Kingdom, France, the United States – plus Germany. Under the JCPOA, Iran wound down its nuclear program in exchange for relief from economic sanctions.
On May 8, US President Donald Trump announced Washington would no longer be a party to and would restore wide-ranging sanctions on Iran. Trump said he wanted a broader pact. Other parties to the agreement have shown unwillingness to follow the US example.
Juncker warned EU member states against being tempted into bilateral pacts with the United States, which would weaken the bloc’s hand in the trade row.
“We must defend our interests and values. And we must act as one. I urge EU nations to resist the temptation to go after bilateral deals with the US. This would weaken Europe,” he said.
EU foreign policy chief Federica Mogherini said on Friday that the bloc and China share commitments to preserve the nuclear agreement.
“Indeed, we are one hundred percent determined to continue cooperation between China and the European Union, but I can add also with Russia, as it belongs to the signatory countries, but also with other partners internationally who are committed to preserve the nuclear deal and its full implementation,” the senior EU official said.
Mogherini added that she held talks with the Chinese foreign minister on the "key" issue of the full continued implementation of the nuclear deal that has been the result of twelve long years of diplomatic work.
Also on Monday, Mogherini said the 28-nation bloc is determined to save the JCPOA despite the United States withdrawal.
She added, “You know that we have been acting already at European Union level to put in place a set of measures to make sure that the nuclear agreement is preserved and the economic investments from the European side, but also from other sides in the world are protected.”
Sputnik and Press TV contributed to this story.