Russian Foreign Minister Sergei Lavrov and US Secretary of State Hillary Clinton
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US-Russia nuclear treaty is in force

A nuclear-arms reduction treaty which has been a cornerstone of President Barack Obama's attempts to rebuild US relations with Russia has come into effect.

US Secretary of State Hillary Clinton and Russian Foreign Minister Sergei Lavrov exchanged papers ratifying the Start treaty at the international security conference in Munich.

The BBC's Tim Allman reports.

  • 06 Feb 2011
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