The Saudi-led coalition was responsible for more than half the children killed and injured in Yemen's civil war last year, United Nations Secretary-General Antonio Guterres has said.
A draft report obtained by The Associated Press said the UN verified 1,340 casualties and attributed 683 - representing 51% - to attacks carried out by the coalition.
It said nearly three-quarters of attacks on schools and hospitals - 38 of 52 - were also carried out by the coalition.
The draft report on children and armed conflict echoes similar findings from last year when the US-backed coalition was put on a UN blacklist for violating child rights.
But 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 Mr Ban stood by the report, which said the UN verified a total of 1,953 youngsters killed and injured in Yemen in 2015 - a six-fold increase compared with 2014.
Foreign Policy magazine reported on Wednesday that Virginia Gamba, the new UN special representative for children and armed conflict, intends to recommend the Saudi-led coalition be added to the list of countries that kill and maim children.
UN deputy spokesman Farhan Haq told reporters on Thursday that Mr Guterres has not 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.
Mr Haq said Mr Guterres is scheduled to meet Ms Gamba on Friday but the report is not expected to be completed for another month.
Saudi Arabia's UN Mission said 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".
Yemen, which is on the southern edge of the Arabian Peninsula, has been engulfed in civil war since September 2014, when Houthi Shiite rebels swept into Sanaa and overthrew President Abed-Rabbo Mansour Hadi's internationally recognised government.
In March 2015, the Saudi-led coalition began a campaign against Houthi forces allied with ousted President Ali Abdullah Saleh in support of Mr 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.