Russia's war in Ukraine has displaced some 4.3 million children in the past month — more than half of the country's estimated 7.5 million child population, according to UNICEF.
The organization said Thursday that this figure includes some 2.5 million children who are now internally displaced inside Ukraine, and more than 1.8 million who have crossed into neighboring countries as refugees.
The ongoing conflict has created one of the fastest large-scale displacements of children since World War II, UNICEF Executive Director Catherine Russell said in a statement.
"This is a grim milestone that could have lasting consequences for generations to come," Russell added. "Children's safety, wellbeing and access to essential services are all under threat from non-stop horrific violence."
Overall, the war has displaced 1 in 4 Ukrainians. Ten million people have left their homes since Russia invaded Ukraine on Feb. 24, with more than 3.6 million refugees fleeing to neighboring countries.
While most want to stay in Europe, the Biden administration said Thursday that the U.S. will welcome up to 100,000 Ukrainians and other displaced people fleeing the conflict.
Russian strikes have also damaged civilian infrastructure and limited access to health care, education and other basic services across the country.
On Thursday, the World Health Organization said it had verified 64 attacks on Ukraine's health care system in just 25 days, averaging two or three per day. UNICEF says that officials have already seen a drop in vaccinations for routine and childhood immunizations like measles and polio.
"This could quickly lead to outbreaks of vaccine-preventable diseases especially in overcrowded areas where people are sheltering from the violence," it adds.
Ukraine's Ministry of Education and Science has reported damage to more than 500 education facilities (some of which have been used as civilian shelters).
UNICEF says that some 4.6 million people have limited access to safe water — with an estimated 1.4 million lacking access entirely — and that more than 450,000 children between the ages of 6 months and 23 months now need complementary food support.
"UNICEF continues to appeal for an immediate cease-fire and for the protection of children from harm," Russell said. "Essential infrastructure on which children depend, including hospitals, schools and buildings sheltering civilians, must never come under attack."
In the meantime, the organization is taking steps to help families and children in the region.
UNICEF says it's delivered medical supplies to hospitals across Ukraine, improving access to health care for 400,000 mothers, newborns and children. It's also increasing the number of mobile child protection teams working inside conflict zones from 22 to 50. And it plans to "start emergency cash transfers to the most vulnerable families and establish child friendly spaces in key locations across the country."
The U.N. Human Rights Office confirms that 78 children have been killed and 105 injured in Ukraine, but says those figures are likely a significant undercount.
This story originally appeared on the Morning Edition live blog.