Russian Deputy Foreign Minister Sergey Ryabkov and his Iranian counterpart Abbas Arakchi met in Tehran, Moscow said on Thursday.
A day earlier, the Ministry of foreign Affairs of the Russian Federation issued a statement condemning the U.S. decision to withdraw from the agreement.
The Kremlin meanwhile accused Trump of "veiled protectionism" by pulling out of the deal.
"We are extremely concerned that the United States is once again acting contrary to the opinion of the majority of states and exclusively in its own narrow-minded and opportunistic interests, in flagrant violation of worldwide law", said the Foreign Ministry statement. This means that the US is out of the "nuclear contract", signed by the powers with Iran in 2015.
All of the U.S.'s negotiating partners - the U.K., France, Germany, Russia, China and the European Union - had agreed that maintaining the JCPOA was the best way to reign in Iran's program.
Foreign Minister Sergei Lavrov on Thursday called on countries that oversaw the deal to "develop steps that would preserve this document that is important for regional stability".
The top Russian diplomat, who was speaking in a joint press conference with his German counterpart Heiko Mass in Moscow, further said, "We agree to make the appropriate contacts with our German colleagues".
Iranian President Hassan Rouhani said Tuesday that his country will stay in the deal with other signatories.