NATO must do more to protect civilians in Afghanistan's worsening conflict, Human Rights Watch said Wednesday, ahead of a summit in Poland set to renew international support for the Afghan army.
The HRW statement came as Afghan President Ashraf Ghani issued a stern warning to the Taliban to join peace negotiations "or face the consequences".
With civilian casualties soaring past 11,000 in 2015, according to the UN, governments in the North Atlantic Treaty Organization have "a crucial opportunity" to help halt the spiralling violence, said HRW's Asia director Brad Adams.
"NATO should deliver on its pledges and produce concrete measures to help protect Afghan civilians from armed conflict," he said ahead of the summit in Poland on Friday and Saturday.
The international rights organization denounced the use of children in conflict by both the Taliban and the Afghan government.
In particular, it slammed the occupation of schools by Afghan forces, saying it had recently identified "extensive" use of school buildings as military bases in northern Baghlan province.
The UN Assistance Mission in Afghanistan (UNAMA) also reported 20 schools occupied by the army or the insurgents last year.
"Too often, the schools become battlegrounds," said HRW.
The "devastating" impact on education has a disproportionate effect on girls, who are unlikely to be allowed to attend schools occupied by male soldiers, the statement noted.
And it sharply criticized the use of child soldiers by both the Taliban and government-backed forces.
An exclusive AFP report recently documented how the Taliban are exploiting children being kept as sex slaves by police commanders in Uruzgan province, recruiting them for insider attacks against security forces.
The UN has said cases of child recruitment more than doubled in 2015 compared to the previous year.
Asked what "concrete measures" NATO could take to slow child recruitment, the organisation's top civilian representative in Kabul Ismail Aramaz said it has "insisted" that its Afghan partners bring those responsible to justice.
"But it is up to Afghans to decide how such acts can be penalised," he added.
In a statement marking Eid al-Fitr Wednesday, Ghani called on the Taliban to take part in peace negotiations.
The insurgents have stepped up their nearly 15-year war since NATO pulled most of its forces out of the country at the end of 2014, while a nascent peace process has stalled.
"The door is open... we do not want bloodshed," Ghani said.
But, he added, if the Taliban reject his call they must "face the consequences".