UN chief Ban Ki-moon spotlighted the plight of children in war-torn Syria Friday, saying more than 2 million were not getting an education due to the bloody, three-year conflict.
Some 40 percent of schools have been damaged or used as shelter by people fleeing their homes, the secretary general added.
"More than two and a quarter million (Syrian) children are out of school," Ban told the UN Security Council during a debate about children in armed conflicts.
"In too many war zones around the world, schools and hospitals have been targeted or caught in cross-fire."
He added that one in five public hospitals in Syria have also stopped functioning due to the war that has killed more than 140,000 people since March 2011.
"The killing and maiming of children and attacks on schools and hospitals continue unabated and children are recruited and used by various armed groups," Leila Zerrougui, Ban's special representative for children and armed conflict, told the council.
Signup to our newsletter and follow us on Facebook and Twitter!
"We cannot afford a lost generation in Syria," she said.
Turning to the Central African Republic, Zerrougui said the conflict there continued to have a "devastating" impact on children. Meanwhile in South Sudan, she warned, more than half the population were children.
On Thursday, Zerrougui and UNICEF, the UN's children's agency, launched a campaign to stop the recruitment of child soldiers by 2016.
"It is time to make child soldiers history ... my firm belief is that this goal is an achievable one," Zerrougui said of the campaign, titled "Children, Not Soldiers."
The council on Friday unanimously adopted a resolution recalling the importance of better protecting children during war and to hold those responsible for abuses against them accountable under international law.
The measure contains non-binding commitments to limit the impact of conflict on schools and invites member states to include mechanisms for child protection in peacekeeping missions and peace deals.
The first UN Security Council resolution on children in conflict was adopted 15 years ago.