The United States and Russia formally inaugurated their new START nuclear arms treaty today, capping two years of work to "reset" the sometimes strained ties between the former Cold War enemies.
US Secretary of State Hillary Clinton and Russian Foreign Minister Sergei Lavrov exchanged the final START documents at the Munich security conference, where two
years ago US Vice President Joe Biden launched the Obama administration's push for better relations with Moscow.
"Two years ago we all laughed about the translation of the ceremonial 'reset' button I gave to the Foreign Minister," Ms Clinton said, referring to a diplomatic gaffe in which she presented Mr Lavrov with an oversized button on which "reset" was mistranslated into the Russian for "overcharge".
"But when it came to the translation that mattered most, we turned words into action to reach a milestone in our strategic partnership."
Russian President Dmitry Medvedev and US President Barack Obama signed the deal in April after a year of tough negotiations, committing the world's top two nuclear powers gradually to reduce their atomic arsenals.
The START treaty has been at the centre of Washington's effort to improve ties with Moscow, which hit a low with Russia's 2008 war against pro-western Georgia and were further strained by disagreements on trade and US concerns over Russia's record on human rights and free speech.
US officials say the "reset" has delivered results on a number of fronts including efforts to rein in the nuclear ambitions of Iran and North Korea, cooperation on the halting Middle East peace process and growing ties between Russia and NATO.
The START treaty itself is also seen as an important step toward Mr Obama's goal of nuclear disarmament - though analysts say there are much higher hurdles ahead if further progress is to be made.