I am writing to you on behalf of Médecins Sans Frontières (MSF) to implore you to do everything within your power to ensure an immediate and sustained ceasefire in the Gaza Strip. You must demand that the Israeli government stop the deadly attacks on Palestinian civilians and allow crucial humanitarian aid to enter Gaza.

A seven-day truce, after weeks of relentless violence, was a welcome respite for the people of Gaza. However, these seven days were not nearly enough to organise the delivery of sufficient aid and essential supplies, to meet the immeasurable needs. Now that the truce has ended, there is a return to death and destruction.

My colleagues and I, like so many people around the world, were distressed and shocked by Hamas’s attack on Israeli civilians. Now, after 58 days, words fail us to describe the absolute horror being inflicted on Palestinian civilians by Israel as it carries out incessant and indiscriminate warfare in Gaza for all the world to see.

Israel has shown a blatant and total disregard for the protection of Gaza’s medical facilities. We are watching as hospitals are turned into morgues and ruins. These supposedly protected facilities are being bombed, are being shot at by tanks and guns, encircled and raided, killing patients and medical staff. The World Health Organization (WHO) has documented 203 attacks on health care that have led to at least 22 fatalities and 59 injuries of health workers on duty. Medical staff, including our own, are utterly exhausted and in despair. They have had to amputate limbs from children suffering from severe burns without anaesthesia or sterilised surgical tools. Due to forcible evacuations by Israeli soldiers, some doctors have had to leave patients behind after facing the unimaginable choice between their lives or those of their patients. There is no justification for the atrocious attacks on healthcare.

MSF recently sent an international emergency team to Gaza to support our Palestinian colleagues in providing medical and surgical capacities. Regrettably, their activities have been severely limited due to the scale of casualties, destruction of infrastructure, lack of essential supplies such as fuel, and the ongoing insecurity. We want and ought to be able to do so much more. Today it is impossible for us to adequately respond to medical needs in Gaza due to the siege and the unrelenting, generalised warfare being unleashed by Israel.

Four of our MSF staff have been killed; many more have lost family members. Numerous other colleagues have been injured. Other humanitarian organisations have reported dozens of their staff have been killed.

Gaza, under an Israel-imposed blockade since 2007, is indeed the world’s largest open-aired prison. From the start of its military campaign on 7 October, the Israeli government has enforced a “complete siege” on Gaza, banning the entry of water, food, fuel and medicinal supplies for the 2.3 million people trapped in the enclave. Added to this, unyielding restrictions have been put on humanitarian access and are preventing much needed aid from reaching anyone who needs it. Subjecting an entire population to collective punishment is a war crime under International Humanitarian Law (IHL).

We are witnessing the fundamental principle of humanity being openly disgraced.

Despite Israel’s claims, its all-out assault is not being waged just on Hamas. It is being waged on all of Gaza and its people at any cost. Even wars have rules, but Israel is clearly trading them in for its own military strategy based on disproportionality. In the early days of this unbearable offensive, the spokesman for Israel’s Defence Forces (IDF) announced that the “emphasis” of this flagrantly excessive reprisal was to be on “damage and not accuracy”. It is safe to say Israel’s actions have spoken louder than its words.

Northern Gaza is being erased from the map. The health system has collapsed. More than 15,500 people have been killed, half of whom are children, according to Gaza’s health authorities. That’s one out of every 200 people in Gaza. Tens of thousands of people have been injured. Families are digging their dead loved ones out from under the rubble. At least 1.8 million people have been displaced, according to the United Nations. These civilians are being repeatedly and forcibly ordered to move further and further south, but Israel is bombing the entire Strip. Nowhere is safe.

Our emergency team in Khan Younis, in southern Gaza, has reported massive influxes of wounded after intense bombing. Last Saturday, 60 dead and 213 injured people arrived at the emergency room of Al-Aqsa hospital. These strikes are also hitting overcrowded, squalid refugee camps, where people are barely surviving on the sparse humanitarian aid available. If the bombs do not get them, infectious diseases and starvation will.

A sustained ceasefire is the only way to stop the killing of thousands of more civilians and allow for the scaled-up delivery of desperately needed humanitarian aid. MSF also calls for the establishment of an independent mechanism to oversee the adequate flow of humanitarian supplies into Gaza. Furthermore, we call for the implementation of secure and long-lasting medical evacuation routes to third countries for people suffering from severe injuries. In the short-term, the evacuation of these patients to Egypt through the Rafah crossing could be an option, and MSF is willing to contribute to scaling up necessary medical capacities.

Indiscriminate and relentless attacks must stop now.      Forcible displacement must stop now.

Assaults on hospitals and medical staff must stop now.   Restrictions on aid and the siege must stop now.

It must ALL STOP NOW.

We call on you to be part of the solution and exert all means in your power to prevent further carnage.

Our medical teams in the West Bank also report attacks on health care with a surge in violence, persecution and harassment, in which nearly 240 Palestinians have been killed since 7 October, either by Israeli Defence Forces (IDF) or Israeli settlers, according to the United Nations.

Thus far, world leaders, including permanent members of the Security Council, have been complicit, either by providing Israel with diplomatic cover, by supplying Israel with seemingly unconditional military assistance, or by failing to help stem the relentless bloodshed and atrocities being committed in Gaza.

It is time to choose whether the Council will continue issuing half-hearted calls for the respect of international law and the protection of civilians, or will fulfil its international peace and security mandate and exercise its full diplomatic leverage to convince the State of Israel that the death sentence it has handed the people of Gaza is inhumane, indefensible, and cannot continue to be carried out.

We urge you to take action to uphold our shared humanity.

“We did what we could. Remember us.” These are the words our Dr Mahmoud Abu Nujaila, who has since been killed in a hospital strike, wrote on a Gaza hospital whiteboard normally used for planning surgeries. When the guns fall silent and the true scale of devastation is revealed, will the Council and its members be able to say the same?