British Foreign Secretary James Cleverly accused Russia on Monday of trying to obliterate Ukrainian identity and using children as tools of warfare.
Addressing a ministerial-level UN Security Council meeting on Ukraine, Mr Cleverly said more than 19,000 Ukrainian children remain in re-education camps in annexed Crimea and Russia. Their parents are “desperately” searching for them, he added.
A further two and a half million Ukrainian men and women have been deported to Russia.
“These are barbaric crimes. Russia is trying to erase Ukrainian identity and cultural history and they are using children as an instrument of war,” he said.
“But the world is watching and Russia will be held accountable.”
Expressing support for a continuing investigation by the International Criminal Court, Mr Cleverly vowed that no stone would be left unturned until the perpetrators are identified and brought to justice.
The ICC issued an arrest warrant for Russian President Vladimir Putin in March over the issue.
Ahead of his speech in New York, Mr Cleverly announced 14 new sanctions designations in response to “Russia's attempts to destroy Ukrainian national identity”, 11 of which are linked to the forcible relocation of children.
Those sanctioned will be subject to asset freezes and travel bans.
Among those sanctioned include Russia's Education Minister Sergey Kravtsov and the commissioner for children's rights in the Moscow region Ksenia Mishonova.
Russian Culture Minister Olga Lyubimova was also named for “using her position to support the Russian state's damaging anti-Ukrainian policies”.
Germany's Foreign Minister Annalen Baerbock described the harrowing experiences of Ukrainian children who managed to return home.
She pointed to how they were forced to change their names and ages in a deliberate act to obliterate their identities and ensure their parents would never locate them again.
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“When an aggressor does not even stop at children, strategy turns into horrendous inhumanity,” she told council members.
Ukrainian Foreign Minister Dmytro Kuleba expressed disappointment in the UN's top panel for its inability to take tangible steps following Russia's invasion.
“We strongly advocate for a vital element to be included in the future reform of the UN Security Council,” he said.
“This entails removing Russia as a permanent member and revoking their veto power, which they obtained unlawfully. The council and the global community will significantly improve once Russia is no longer a part of it.”
US President Joe Biden is expected to meet Pope Francis' peace envoy, Cardinal Matteo Zuppi, on Tuesday in Washington to discuss the plight of the deported children.
Pope Francis told reporters in May during his visit to Hungary that the Vatican would do “all that is humanly possible” to help bring Ukrainian children home.
