The Saudi Arabia-led military coalition was responsible for an "unacceptably high" number of child deaths and injuries in Yemen last year, according to a draft United Nations report.
The review of children and armed conflict seen by Al Jazeera on Thursday said the United Nations verified 1,340 casualties and attributed 683 - or 51 percent - to attacks carried out by the Saudi-led coalition.
Houthi rebels were responsible for killing or wounding 414 children with al-Qaeda and the Islamic State of Iraq and the Levant (ISIL, also known as ISIS) group blamed for the rest. The study found 502 Yemeni children were killed and 838 wounded in total in attacks.
It said nearly three-quarters of air attacks on schools, 38, and hospitals, 52, were carried out by the Saudi-led alliance.
"We call on all sides to avoid any civilian casualties and particularly that of children. And in Yemen, we particularly call on all sides to permit humanitarian access because the situation there is deeply concerning," Jonathan Allen, deputy UK ambassador to the UN, told Al Jazeera.
The draft report echoes similar findings from last year when the US-backed coalition was put on a United Nations blacklist for violating child rights.
It was removed by then-secretary-general Ban Ki-moon after Saudi Arabia and other coalition supporters threatened to stop funding many UN programmes.
But Ban said he stood by the report, which said the UN verified a total of 1,953 young people killed and wounded in Yemen in 2015 - a six-fold increase compared with 2014.
"Now we know there is a draft with the Saudis' name on it. Let's hope that when the list finally becomes public in a few weeks they'll stay there," Akshaya Kumar, deputy UN director at Human Rights Watch, told Al Jazeera.
Foreign Policy magazine reported on Wednesday that Virginia Gamba, the new UN special representative for children and armed conflict, intends to recommend that the Saudi-led coalition is added to the list of countries that kill and maim children.
UN deputy spokesman Farhan Haq told reporters on Thursday that Secretary-General Antonio Guterres hasn't seen the draft report that was leaked. He said its contents are still under discussion and the decision of who will be on the blacklist is up to him.
Haq said Guterres is scheduled to meet Gamba on Friday but the report isn't expected to be completed for another month.
Saudi Arabia's UN Mission said in a statement that the coalition maintains its position "that there is no justification whatsoever for including its name in the annex of the secretary-general's report on children and armed conflict".
"We trust that the UN will make the appropriate decision on this matter," taking into consideration an ongoing review with the UN and "the positive exchange of information" on the coalition's activities, it said.
Yemen, which is on the southern edge of the Arabian Peninsula, has been engulfed in civil war since September 2014, when Houthi rebels swept into the capital Sanaa and overthrew President Abd-Rabbu Mansour Hadi's internationally recognised government.
In March 2015, the Saudi-led coalition began a campaign against Houthi forces allied with overthrown President Ali Abdullah Saleh in support of Hadi's government. Since then, the Iranian-backed Houthis have been dislodged from most of the south, but remain in control of Sanaa and much of the north.