“Important outcome of my visit to #Iran is that we deblocked recent deadlock and that halted Joint Comprehensive Plan of Action #JCPOA negotiations will resume,” Borrell wrote in a tweet on Saturday night.
The EU's top diplomat met with Iran’s Foreign Minister Hossein Amirabdollahian and Secretary of Supreme National Security Council Ali Shamkhani in Tehran.
Earlier, he had met with the United States Special Envoy for Iran Robert Malley.
Borrell said in a joint press conference with Amirabdollahian that the negotiations would resume and his team would act as a facilitator.
Iran and the P4+1 began a series of talks in Vienna, Austria, for a possible return of the US to the 2015 Iran nuclear deal, formally known as the Joint Comprehensive Plan of Action or JCPOA.
The talks were halted a few months ago, as the US declined Iran’s demands for full enjoyment of the JCPOA economic benefits.
Iran had originally signed the deal to limit its nuclear activities in return for removing sanctions against the country. However, the US unreasonably withdrew from the deal in 2018 and unilaterally resumed all sanctions lifted by the deal.