The State Duma has unanimously ratified the treaties on the accession of the Donetsk and Lugansk People’s Republics (DPR and LPR), as well as Kherson and Zaporozhye Regions, to the Russian Federation.

President Vladimir Putin submitted the documents regarding the four former Ukrainian territories to the lower house of parliament on Sunday. All four voted overwhelmingly in favor of joining Russia in referendums held between September 23 and 27.

Addressing legislators before the vote, Foreign Minister Sergey Lavrov said that accession will “serve the interests of all people of our multiethnic country.”

He added that Kiev had oppressed Russian-speaking people, which made the existence of certain territories within the Ukrainian state impossible.

State Duma Speaker Vyacheslav Volodin argued that accession to Russia is the only way to save the people living in the four former Ukrainian territories from shelling by Ukrainian troops. “The only way to end this is reunification [with Russia],” he said.

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The accession treaties, which were signed by Putin on Friday, were then approved by the Russian Constitutional Court.

The next step in the accession process is ratification by the Federation Council, the upper house of Russia’s parliament.

The DPR and LPR broke off from Ukraine shortly after the 2014 coup in Kiev. Russia recognized them as independent states in February.

Ukraine’s southern Kherson and Zaporozhye Regions were seized by Russian troops during Moscow’s military operation in the neighboring country, which was launched on February 24. They declared independence in the wake of last week’s referendums and, along with the DPR and LPR, requested to be admitted into Russia.

Ukraine, along with Western countries, considers the vote illegal and refused to recognize the accession.