Russian President Vladimir Putin formally integrated four Ukrainian areas into Russia on Wednesday, amid the withdrawal of its troops from key areas in Ukraine and impending additional sanctions from the European Union.

Putin signed into law the annexation of the additional regions, which account for up to 18 percent of Ukraine, part of which is not under Moscow's administration.

Zelensky Vows to Knock Out Russian Forces

According to Reuters, Moscow is staking claim to 22 percent of Ukraine if Crimea is included, which it annexed in 2014. It has not yet specified where all of the boundaries will be, and its soldiers have been forced to withdraw on different fronts. The annexation of eastern Ukrainian cities like Donetsk and Luhansk, as well as southern Ukrainian cities like Zaporizhzhia and Kherson, was completed with the signing of formal documents by the Russian leader.

Kyiv has reclaimed hundreds of thousands of square kilometers of its area in previous weeks. The Russian army appears to be targeting large portions of Ukraine under the rule of the Ukrainian forces, which have been making significant progress in the east and this week also made progress in the south, according to a map released by the state-run media organization RIA.

After staging what it termed referendums over several days beginning on September 23, ballots that were criticized by Kyiv and Western nations as unlawful and coercive, Moscow proceeded with its annexation plan. With the final approval of the annexation by Putin, the Russia Ukraine war has intensified, in which Moscow has launched military mobilization and threats to use nuclear weapons.

Ukrainian President Volodymyr Zelensky vowed to reclaim even more territory from Russian soldiers in the eastern Donbas region. Zelensky stated in his evening address on Saturday that "more Ukrainian flags have been raised in Donbas" and there will be "even more in a week," NDTV reported.

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EU To Slap More Sanctions on Russia in Wake of Annexation

The Ukrainian president made the remarks after Kyiv said its forces had moved into the strategic eastern town of Lyman and the defense ministry broadcast a video of soldiers hoisting a yellow and blue Ukrainian flag in the town. The Russian defense ministry said that Russian soldiers had been "withdrawn" from the city and redeployed to better positions.

Zelensky said Russians will be "knocked out" gradually as long as Vladimir Putin kept his position as Russian president. Calling the Russia Ukraine war a "historic mistake" for the Kremlin, Zelensky warned that Russian officials who initiated the "senseless war" will be eliminated "one by one" until "the one who started it all" solves the conflict.

In a related update from AP News, EU countries reportedly decided Wednesday to slap further penalties on Russia after it unlawfully seized four Ukrainian areas, including a price ceiling on Russian oil.

According to an official of the union, the details of the new sanctions might be released on Thursday. A limit on the cost of Russian oil is likely to be one of them, along with restrictions on the sale of aviation parts and steel to Russia from the European Union.

These measures are in addition to the unusual European penalties imposed on Russia since the start of the war in February. Russian energy imports are currently restricted, financial transactions with Russian institutions, including the central bank, are prohibited, and more than 1,000 individuals and 100 organizations have had their assets frozen.

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