Tehran has triggered the “dispute mechanism” built into the 2015 Iran nuclear deal over compliance issues with France, Germany and the United Kingdom, the EU’s foreign policy chief Josep Borrell reported on Friday.He did not specify what issues led Iran to trigger the mechanism, which could be the first step toward dissolution of the deal, known as the Joint Comprehensive Plan of Action (JCPOA). It was signed in 2015 between Iran and six world powers including: the United States, Russia, China, France, the United Kingdom and Germany.The US withdrew from the deal in 2018, a move that has already significantly weakened the agreement under which Iran was supposed to curb its nuclear program in exchange for sanctions relief. Iran has already breached part of the deal, particularly with regard to limits set on uranium enrichment.Borrell said on Friday, “I have received today a letter from the Foreign Minister of Iran referring Iran’s concerns regarding implementation issues by France, Germany and the United Kingdom under the JCPOA to the Joint Commission for resolution through the Dispute Resolution Mechanism, as set out in paragraph 36 of the agreement.”Any party to the deal can refer non-compliance issues to a Joint Commission that involves representatives of all parties to the deal, plus the European Union. There is then a 30-day two-step process to resolve the matter, with the potential to extend the time frame. If no resolution can be achieved, the deal can be dissolved.“As I have said previously, the Dispute Resolution Mechanism requires intensive efforts in good faith by all. As Coordinator of the Joint Commission, I expect all JCPOA participants to approach this process in this spirit within the framework of the JCPOA,” Borrell said.“The Joint Commission, which is responsible for overseeing the implementation of the agreement under the terms of the JCPOA, has met since 2016 to discuss the implementation of the JCPOA and address pertinent issues brought to the attention of the Coordinator by any participant,” he said.“As we approach the fifth anniversary of the JCPOA, I would like to take this opportunity to recall the importance of the agreement. The JCPOA is an historic achievement for global nuclear non-proliferation contributing to regional and global security. I remain determined to continue working with the participants of the JCPOA and the international community to preserve it,” he added.In January of this year France, the UK and Germany triggered the dispute mechanism, but the issue was resolved.