BEIRUT: Desperate, despondent and under near-constant bombardment, 15 of the last 35 remaining doctors in rebel-held east Aleppo have written an impassioned appeal to U.S. President Barack Obama, pleading he intervene and help cease the bombings the city is subjected to.

The signatories decry U.S. inaction, the United States’ failure to protect Syrian civilians and its tolerance of Russian and Syrian regime crimes.

“The burden of responsibility for the crimes of the Syrian government and its Russian ally must therefore be shared by those, including the United States, who allow them to continue,” the doctors write.

The plea comes in the wake of a monthlong siege of the eastern part of the city that was tentatively lifted by rebels Saturday, and the doctors ask Obama to ensure the people there are never subjected to that treatment again.

“The siege has been lifted, perhaps temporarily, but not by diplomacy,” the letter states. “Whether we live or die seems to be dependent on the ebbs and flows of the battlefield.”

Syrian regime forces, backed by Russian air power, deprived the rebel-held neighborhoods of Syria’s former commercial capital of food, water and medical aid for over a month.

Since a rebel counteroffensive lifted the siege some food aid has trickled through thanks to local initiatives from opposition groups. Yet east Aleppo remains the target of heavy Russian and regime bombing, which in recent weeks has intensified and targeted many medical facilities.

According to the letter, last month saw 45 attacks on medical facilities across the country, 15 of which the signatories work in. At the time of writing, it says, there is an attack on a medical facility every 17 hours.

“At this rate, our medical services in Aleppo could be completely destroyed in a month, leaving 300,000 people to die.”

They describe to Obama their pain at the choices they have to make over who lives and who dies. “Young children are sometimes brought into our emergency rooms so badly injured that we have to prioritize those with better chances, or simply don’t have the equipment to help them.”

The letter describes a bombing attack on a pediatrics center two weeks ago which killed four infants.

“Four newborn babies gasping for air suffocated to death after a blast cut the oxygen supply to their incubators. Gasping for air, their lives ended before they had really begun.”

The doctors say as medical professionals they have a duty to remain in Aleppo to help those in need, despite the risk of airstrikes and another siege.

“Mr. President, we ask that you do the same.”

During the siege Russia and the regime offered rebel-held areas evacuation, an offer, the doctors say, that sounded like a thinly veiled threat.

And Russia Wednesday announced three-hour daily cease-fires to deliver aid to Aleppo, a strategy dismissed by the United Nations’ top aid official as inadequate for the city’s needs.

But for the doctors, only assistance from international friends, rather than those attacking the city, can end the threats its people face.

“We do not need tears or sympathy or even prayers, we need your action. Prove that you are the friend of Syrians.”