"There are no deadlocks in the Vienna talks and we have reached key issues," Xinhua news agency quoted Foreign Minister spokesman Saeed Khatibzadeh as saying at a press conference on Monday.

His remarks were made a reference to the ongoing negotiations between Iran and the P4+1, namely the UK, China, France, Russia plus Germany, aimed at the revival of the nuclear deal, commonly known as the Joint Commission of the Joint Comprehensive Plan of Action (JCPOA).

"We are in no hurry to reach an agreement and we will not allow the negotiations to erode," Khatibzadeh said.

The spokesman urged US President Joe Biden not to follow "the legacy of the previous administration".

The US government under former President Donald Trump withdrew from the JCPOA in May 2018 and unilaterally re-imposed sanctions on Iran.

In response, Iran gradually stopped implementing parts of its JCPOA commitments from May 2019.

Biden has promised to return to the deal and ease sanctions against Iran.

The JCPOA Joint Commission began to meet on April 6 in Vienna to continue the discussion about a possible return of the US to the deal and how to ensure the full and effective implementation of the agreement.