After an exchange of ratification documents between the United States and Russia, which took place in Munich on February 5, 2011, the New START treaty formally entered into force.

Among other things, this means that the United States and Russia will resume data exchange no later than March 20 - the treaty gives 45 days to prepare initial declarations. Presumably, both countries started the process already, since declarations will have to include individual numbers for all strategic launchers and tagging all launchers would probably take some time.

The entry into force also sets into motion a few other processes, summarized by the State Department.