WARSAW, Poland — The European Union has voiced its worries over Sunday’s Belarusian referendum which enables the authorities there to modify the constitution’s article describing Belarus as a “nuclear-free zone” and a “neutral” state, potentially allowing Russia to deploy additional nuclear weapons along NATO’s eastern flank.

Josep Borrell, the head of the European Union’s foreign affairs and security policy, said in a tweet Monday the vote was carried out by Belarusian president Alexander Lukashenko “to gain additional tools to further consolidate his power.”

“The deletion of Article 18 on Belarus’s non-nuclear status is greatly worrying,” Borrell said.

The development comes amid Russia’s invasion of Ukraine and intensifying threats by the former country’s president, Vladimir Putin, directed at the West. The authoritarian leader has warned NATO allies that their interference in Moscow’s war against Kyiv could lead to a nuclear conflict in Europe.

Organized on the initiative of Lukashenko, who remains one of Putin’s closest foreign allies, the constitutional referendum had a turnout of 78.6 percent, of which 65.2 percent were said to approve the proposed amendments, according to official data released by the state-run Central Election Commission.

Numerous Western organizations, such as the Stockholm-based International Institute for Democracy and Electoral Assistance, have decried the referendum as “held in an environment of fear and repression,” and the vote was accompanied by mass arrests of protestors.

Lukashenko’s regime has long depended economically and militarily on the Kremlin’s support. On Feb. 24, Belarus facilitated Russia’s attack on Ukraine by allowing Russian tanks to roll across the Belarusian-Ukrainian border.

Last November, Lukashenko announced Minsk was in talks with Moscow to acquire Iskander missile systems for the Belarusian armed forces. This would allow Belarus to increase its missile launchers’ range from about 300 km (186 miles) to 500 km (311 miles), he said.

Jaroslaw Adamowski is the Poland correspondent for Defense News.

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