Russia–United States relations when Russia and Georgia fought a five-day war over the Russian-backed self-proclaimed republics of South Ossetia and Abkhazia. Despite U.S.–Russia relations becoming strained during the Bush administration, Russian president Dmitry Medvedev (president from May 2008 until May 2012, with Vladimir Putin as head of government) and U.S. president Barack Obama struck a warm tone at the 2009 G20 summit in London and released a joint statement that promised a "fresh start" in Russia–United States relations. The statement also called on Iran to abandon its nuclear program and to permit foreign inspectors into the country. In March 2009, U.S. Secretary of
Russia–South Ossetia relations travelled to South Ossetia on 21 July 2009, where they attended the opening of two rural police stations, and attended the signing of an interagency agreement between the two countries prosecutorial agencies. On 7 August 2009, Dmitry Medvedev in an interview for the documentary "In August 2008..." stated that Russia would continue to develop bilateral ties with South Ossetia "regardless of whether somebody likes it or not." The Treaty of Friendship, Cooperation and Mutual Assistance which was signed in September 2008 came into force on 20 January 2009, and stipulates a Russian guarantee of military intervention in case South Ossetia