By Sean Coughlan, BBC
Prince William has called for an "end to the fighting as soon as possible", in a strongly worded intervention on the Israel-Gaza conflict.
He has spoken of the "terrible human cost of the conflict in the Middle East since the Hamas terrorist attack".
Prince William said there is a "desperate need for increased humanitarian support to Gaza" and for hostages to be released.
His statement came as he visited the British Red Cross in London.
It is understood the government had been briefed about the prince's statement and his visits, via the Foreign, Commonwealth and Development Office.
"Too many have been killed," said the prince, who was told by Red Cross workers about the humanitarian efforts to support people caught up in the conflict in the Middle East.
The prince took part in a video link with Red Cross staff in Gaza, who gave him first-hand accounts of their work.
He heard about the medical support being provided and also the "psycho-social" mental health help for those traumatised by the loss and destruction.
"It is civilians who pay the price as the humanitarian situation continues to deteriorate," said Beatrice Butsana-Sita, British Red Cross chief executive.
Prince William is carrying out visits this month intended to recognise the human suffering and distress from the Israel-Gaza war.
He is said to have felt strongly about what has happened in the Middle East and is said to be "deeply moved as a father".
"Sometimes it is only when faced with the sheer scale of human suffering that the importance of permanent peace is brought home," said the prince.
On another visit to a synagogue later this month Prince William will speak to young people from a range of backgrounds, in a meeting which will draw particular attention to concerns about antisemitism.
The building of bridges between faiths, and tackling religious intolerance, has been a particular cause of the prince's father, King Charles III.
But since the King's cancer diagnosis earlier this month, he has not been carrying out such public visits.
Last October, the King spoke of the "heartbreaking loss of life" in the Middle East conflict and made an impassioned call for respect between different faiths and cultures.
And in his Christmas message, he spoke of the underlying universal values shared by religions, at a time of "tragic conflict".
But with the King stepping back from such public involvement during his cancer treatment, Prince William will be among the senior royals taking on such symbolic and sensitive visits.
This story was originally published by the BBC.