The deal described by Russian presidential aide Sergei Prikhodko as "very timely" was signed in the presence of Russian President Dmitry Medvedev and Indian Prime Minister Manmohan Singh.
Russia has so far been the only country involved in nuclear cooperation projects with India, Prikhodko said.
Medvedev and Singh also adopted a joint declaration confirming their countries' intentions to continue cooperation in the Kudankulam project in the southern province of Tamil Nadu and build more NPPs across India.
The facilities to be built will be backed by IAEA guarantees throughout their life term.
The Russian nuclear power chief, Sergei Kiriyenko, said earlier Russia and India would also sign a protocol on supplying $700 million worth of nuclear fuel to India.
Russia's state-run nuclear fuel manufacturer TVEL and an Indian national corporation are expected to sign the protocol in New Delhi later Friday.
Atomstroyexport, Russia's nuclear power equipment and service export monopoly, has been building two reactors for the Kudankulam plant since 2002 in line with a 1988 deal between India and the Soviet Union and an addendum signed 10 years later.