An agreement between Russia and the United States on cooperation in the peaceful use of nuclear energy officially came into effect on Tuesday.The Agreement 123 took force after Russian Deputy Foreign Minister Sergei Ryabkov and U.S. Ambassador to Russia John Beyrle exchanged relevant diplomatic notes in Moscow. The Russian diplomat told reporters that with the entry into force of Agreement 123 there has been a turn of an important page in US-Russia relationship, which allows to increase cooperation in civilian nuclear power. Beyrle said this document allows for the transfer of American nuclear technology, materials and equipment to Russian partners, and thereby opens up opportunities for cooperation on new levels. Signed on May 6, 2008, the intergovernmental agreement was later invigorated as U.S. President Barack Obama targeted the resetting of relations between Russia and the United States as one of his top foreign priorities.