The Federation Council voted unanimously on Friday to ratify a treaty that will begin the process of absorbing Crimea into the federal structure of Russia.
Foreign Minister Sergei Lavrov, who presented the treaty to the State Duma on Thursday, set the tone for the latest vote by criticizing Western characterizations of Russia's action in Ukraine as an annexation.
"When terms like 'annexation' are thrown around, I consider it to be an insult to [local] citizens and their right" to self-determination, Lavrov told the Federation Council, Interfax reported.
The State Duma on Thursday voted 443 to 1 to approve the treaty.
It now remains for President Vladimir Putin to sign the treaty into law, which he is set to do later Friday, Reuters reported.
The process of Crimea's integration into Russia will be conducted throughout the rest of 2014, culminating in the region's full accession on Jan. 1, 2015
The treaty stipulates that elections for new Crimean authorities will take place in September 2015, Interfax reported.