United States Secretary of State Hillary Clinton has held talks in Moscow with Russian foreign minister Sergei Lavrov.
Mrs Clinton says they've agreed to pursue a diplomatic course against Iran over its nuclear programme.
But the BBC reports from Moscow, there was no agreement on new sanctions against Iran.
Mr Lavrov said on Tuesday that threatening further sanctions against Iran over its nuclear programme would be counter-productive. He said every effort should be made to continue negotiations.
Mrs Clinton has warned the world will not "wait indefinitely" for proof that Iran is not making nuclear weapons.
Iran disclosed to the international Atomic Energy Agency on 21 September that it has a second uranium plant, near the city of Qom.
Iran says its nuclear programme is for peaceful energy purposes, but the US and other Western nations believe it is seeking nuclear weapons.
Putin in China
The BBC reports Mrs Clinton will not meet Prime Minister Vladimir Putin during her visit to Russia. He is in China for talks focusing on trade, but also expected to raise the nuclear programmes of Iran and North Korea.