More than 16,000 children are believed to have been transferred to Russia or Russian-controlled territory from Ukraine since fighting began.
Moscow intends to return all Ukrainian children transferred to Russia when the conditions are safe, the country's envoy to the United Nations said on Monday.
More than 16,000 children are thought to have been transferred to Russia or Russian-controlled areas from Ukraine since the fighting began, according to Ukrainian government figures.
UN investigators have said these forced deportations amount to a war crime.
"We wanted to spare them of the danger that military activities may pose," Vasily Nebenzya, Russia’s Permanent Representative to the UN, was quoted as saying by the Russian state news agency TASS.
"That is it."
The Russian diplomat hit back against widespread international condemnation, saying the issue of children forcefully brought to Russia was "totally overblown".
"When conditions are safe, of course, why not," he added.
On Friday, the International Criminal Court issued an arrest warrant for Russian President Vladimir Putin over the "unlawful deportation" of children from occupied areas of Ukraine.
"There are reasonable grounds to believe that Mr Putin bears individual criminal responsibility for the aforementioned crimes," it said in a statement.
The arrest warrant was condemned by the Kremlin, with its press secretary Dmitry Peskov calling it "outrageous and unacceptable".
Russia does not recognise the jurisdiction of the court, he added.
In March, the UN Commission of Inquiry on Ukraine said there was evidence of the illegal transfer of hundreds of Ukrainian children to Russia.
Its report noted that Russia is placing Ukrainian children in foster families to "create a framework in which some of the children may end up remaining permanently" in Russia.
Investigators wrote these transfers often "became prolonged", while the children themselves were subjected to mistreatment, forced to wear "dirty clothes" and "screamed at" in some cases.
It quoted witnesses claiming smaller children may not be able to contact their families and "lose contact with them indefinitely".
The report concludes that forced deportations of Ukrainian children "violate international humanitarian law, and amount to a war crime".
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