Russia's upper chamber of parliament, the Council of Federation, unanimously ratified agreements on four Ukrainian regions joining Russian territory.
On Monday, all members of Russia's lower chamber of parliament, the State Duma, also voted in favor of the agreements on incorporating the Donetsk, Kherson, Luhansk, and Zaporizhzhia regions into Russia.
After both chambers of the Russian parliament approved the documents, Russian President Vladimir Putin will sign them into law.
Necessary amendments to the Russian constitution will also be made as it stipulates the number of the country's regions and other issues of territorial organization.
Last Friday, Russian President Vladimir Putin signed agreements with separatist authorities of four Ukrainian breakaway regions on joining Russia, following referendums held on Sept. 23-27.
The referendums have been condemned by the international community, with European nations and the US calling them a "sham" and underlining that they would not be recognized.
Calling Moscow’s move "a grave violation of the established principles of international law,” Türkiye also said: “We reject Russia’s decision to annex the Donetsk, Luhansk, Herson, and Zaphorizhia regions of Ukraine."