Iranian president Ebrahim Raisi told the Russian parliament on Thursday his country was not seeking to get nuclear weapons.
In a speech at the State Duma, Raisi said Iran was serious about reaching an agreement to limit its nuclear program, but would not agree to anything less than its "rights".
"We are not after nuclear weapons, and such weapons have no place in our defensive strategy," he added.
Russia has actively taken part in international talks in Vienna aimed at salvaging Iran’s tattered 2015 nuclear deal with world powers.
The United States withdrew from the accord in 2018 under then-President Donald Trump, while President Joe Biden wants to rejoin the deal.
"We can bring these talks to a successful conclusion and address the core concerns of all sides. But time is running out," Biden said, adding that "if a deal is not reached in the coming weeks, Iran's ongoing nuclear advances, which resumed after we withdrew from the agreement, will make it impossible for us to return to the JCPOA."
The 2015 agreement was intended to rein in Iran’s nuclear programme in return for loosened economic sanctions.
Raisi, who is in Moscow for an official visit, met with Russian President Vladimir Putin the previous day.
Meanwhile, Iran, Russia, and China are set to begin a three-day joint naval drill in the Indian Ocean on Friday, in a bid to reinforce "common security", according to an Iranian naval official.
The spokesman for the exercises, Admiral Mustafa Tajeddini, told state television that they would include "the participation of 11 naval units from the armed forces of Iran, three units from the Revolutionary Guards' navy, three units from Russia and two units from China."
He added that they would take place over an area of 17,000 square kilometres in the northern Indian Ocean.
Tajeddini claims they aim to "enhance capabilities and combat readiness, strengthen military ties between the Iranian, Russian and Chinese navies, ensure common security and counter maritime terrorism".
The three countries held similar drills in the Gulf of Oman and the Indian Ocean in late 2019, when tensions had risen between Iran and its US-allied Arab neighbours in the Gulf.