Russia has signed a contract to build two more nuclear reactors in Iran to be possibly followed by another six, a move intended to cement closer ties between the two nations.

Russia and India signed weapons deals worth billions of dollars today as president Vladimir Putin sought to further boost ties with an old ally.

Russia's nuclear chief says Iran would like more Russian-built nuclear reactors following the launch of its first that began producing electricity in September.

Iran’s leadership was today furious over Russia’s refusal to ship fuel for its first nuclear power plant, signalling a possible break in a long-time alliance that has helped protect Tehran from tough UN sanctions.

Russia’s top nuclear official said today that his country tightly controls all exports of polonium, the radioactive isotope that British authorities suspect killed former KGB agent Alexander Litvinenko in London.