Six Ukrainian children will be returned from Russia to their families in Ukraine, the White House said on Thursday, citing efforts by first lady Melania Trump to expedite their return.

A seventh Ukrainian child will also be returned to their family later this month, the first lady's office said in a statement.

Ukraine says close to 20,000 children have been illegally sent to Russia and Belarus, where they are sometimes subject to military training and forced to fight against their own country's troops.

Melania Trump wrote to Russian President Vladimir Putin in August about the plight of Ukrainian children separated from their families by war. It was the fourth time the U.S. first lady had expedited such a return, the White House said.

"Reunifying children with their loved ones in this region of the world remains one of the most important global issues today. I am encouraged that both sides remain committed to ongoing cooperation, raising the safety and well-being of children above this abhorrent war," the statement said.

A U.N. investigation found last month that Russia's deportation and transfer of Ukrainian children since Moscow's full-scale invasion in 2022 amounted to crimes against humanity. The International Criminal Court has issued arrest warrants for President Vladimir Putin and five other Russians over illegal deportation of children.

Moscow denies it is taking children against their will, saying it has been evacuating people voluntarily to remove them from a war zone.