ALEPPO, Syria / WASHINGTON

All hospitals in the besieged city of Aleppo in northeastern Syria have been forced to shut down due to relentless airstrikes by the regime and Russian warplanes, according to the city’s opposition-run health directorate. 

In a statement Friday, the directorate said all hospitals in the city’s eastern parts have been forced to suspend operation as a result of the ongoing attacks by regime and Russian forces. 

“The regime army and Russian forces are using all kinds of weaponry to bomb civilians and infrastructure in order to prevent civilians, including women, the children, and elderly, from receiving medical treatment,” it said. 

The health directorate called on all world governments “to intervene at once to stop the war crimes in Aleppo”. 

The U.S. condemned the destruction of hospitals in the city under siege.

“There is no excuse for these heinous actions,” National Security Advisor Susan Rice said in a statement.

Rice said that during his visit to Europe this week, President Barack Obama had reiterated his demand for an immediate halt to the bombardment of hospitals, adding that he would bring the issue up at the Asia-Pacific Economic Cooperation (APEC) summit starting Saturday in Peru.

“The Syrian regime and its allies, Russia in particular, bear responsibility for the immediate and long-term consequences these actions have caused in Syria and beyond,” she added.

At least 150 civilians have been killed and hundreds injured in relentless attacks by regime and Russian warplanes on war-battered Aleppo in the past three days. 

Syria has been locked in a devastating civil war since early 2011, when the Bashar al-Assad regime cracked down on pro-democracy protests – which erupted as part of the "Arab Spring" uprisings – with unexpected ferocity. 

Since then, hundreds of thousands of people are believed to have been killed and millions more displaced by the conflict. 

In September of last year, Russia began an extensive air campaign in Syria with the aim of propping up the embattled Assad regime and fighting what it describes as "terrorist groups".